10/7/14 EDIT: Dominique Ansel has just released his cronut recipe, which is more or less in line with mine (some proportions slightly different), will do a comparison later. A key difference between our approaches is that he includes 2 overnight rests, making the entire process last 3 days long, which is unnecessary. The first rest allows for some gluten relaxation and for some very minor gas production by yeast (most is produced during the room temperature proofing step), which overall improve the cronut texture somewhat. The second rest just makes the cooled, laminated dough easier to handle, and allows for even more gluten relaxation. The technique for making cronut dough is roughly the same as puff pastry or croissant dough, which also can potentially take as long as 3 days, but have been done successfully in less. With reduced rests, the whole process would only take ~2 hours, with 1.5 hours proofing time, or about 3.5 hours total, a 95% reduction in preparation time! By keeping only the second overnight rest for better texture, the time savings are still substantial.
For those of y’all less inclined to read, I will write up an explicit recipe for how to make bronuts/cronuts/broissants, if there is sufficient interest. Instead...
Summary/quick tips:
For those of y’all less inclined to read, I will write up an explicit recipe for how to make bronuts/cronuts/broissants, if there is sufficient interest. Instead...
Summary/quick tips:
- Use a regular croissant dough recipe from a reputable source, but adjust the ingredients for lower water content, higher carb content, higher protein content
- After cutting out your donuts, it is CRITICAL to let them "proof" or rise at room temperature for 1.5-2 hours. Helpful tool: donut cutter
- Deep fry at 360 deg F for 90 seconds for a soft exterior, 120 seconds for a crispier exterior. Helpful tool: deep fry thermometer
- Use a grating tool to grate a dark chocolate bar over the cronut for chocolate shaving topping. Helpful tool:microplane
- Use a piping bag with thin tip or a squeeze bottle to pipe beer pastry cream (or other heavy flavor to balance the light cronut) into four points of the cronut. Useful tools: piping bag
or squeeze bottle
As some of you may know, the big new food craze to hit NY is
Dominique Ansel’s “cronut” – a donut shaped pastry with a flaky, layered
croissant interior. A good half the hype
is how rare these seem to be, as only 200 or so are made each day, and are
typically sold out within an hour or two (meaning people typically need to line
up between 5 and 7 AM). One Sunday some
of my friends and I had nothing better to do so we decided to see what all the
fuss was about.
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| Left: The line at 7AM on a Sunday for cronuts. Right two: We did it! Only 8 people from the cutoff |
It was alright, but many of us agreed it was not what we
were expecting. I agreed with some
people’s criticisms I had read online – the lemon pastry cream filling was a
bit sweet and didn’t mesh well with the donut, but my main beef with the donut
was with its texture. I was expecting
something with good contrast – crispier on the outside, soft and buttery on the
inside. This may be more my own personal
preference, since I think most donuts do have this same soft outside, soft
inside, uniform texture. In any case, I
sympathized with some of the people who
barely missed the cutoff, or don’t want to pay $5 for a pastry, or think
that the whole cronut business is snooty and exclusive. For many of these reasons, I decided to go
about building a better cronut.
To create this improved cronut, some background
understanding on three key pastries is necessary: croissants, donuts, and
beignets (bits of fried dough with a pillowy soft inside and a crisp/crunchy
outside). My ideal cronut would have a
beignet’s texture contrast, but be made out of croissant dough and be shaped
like a donut.
 |
| Heat transfer simulation in ABAQUS of a donut-shaped and similar-dimension circular disk of dough fried in 360o F oil, using dough thermal parameters from the Food Properties Handbook, 2nd ed by Rahman. The disk has regions on the interior ~309 K or 96.5 F, vs 321 K or 118 F on the interior of the donut).\ |
| The donut shape: The toroidal shape of donuts is actually an important element here. The frying of dough happens very quickly, on the order of a minute or two. Other people trying to copycat the cronut recipe have noted that just deep frying a croissant results in a raw interior. As I’ve discussed earlier, the key here is the surface area-to-volume ratio. In the figure above, you can see that after 2 minutes frying at the same temperature, if the donut hole is not removed, then the interior of the dough is significantly less cooked (~20 degree difference, dark blue seen in disk, no dark blue in donut). |
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| Fat, water, protein, and carb composition of croissant (n=6), beignet, and yum-yum recipes. The fried recipes appear to have higher fat content and lower water content than the croissant, as well as possibly higher protein content. This chart should put your mind at ease as to how much room for error there is for croissant doughs |
The croissant
dough: Some people may be surprised
to learn that fried croissant dough is actually not that innovative – this
pastry, called a “Yum-Yum” has been around in the UK for decades (maybe
centuries? sorry, I’m not really a food historian). But before I learned about this, I knew that
in order to fry croissant dough, some modifications would be necessary. Alton Brown mentioned in his waffle episode
(The Waffle Truth) that fried doughs typically need higher fat and sugar
content to stand up to frying. To
confirm this, I did what I call a meta-analysis of multiple recipes. This appeared to be the case, as an example
beignet recipe (from cottonseedoiltour.com, based on ones from Café du Monde)
and yum-yum recipe (from James morton)
both had higher carb content, lower water content, and possibly higher protein
and fat content by mass than average croissant doughs (taken from 6 reputable
sources). I chose the one recipe with
highest carb, highest protein, and lowest water content and adjusted these up a
bit more for my first trial.
 |
| Left: Croissant dough initial proof/rising. Center: Making a flat sheet of butter, I like to use an old shopping bag and a wine bottle as a rolling pin. Right: After folding and sealing the dough around the sheet of butter, the dough-butter package was folded into thirds. This three-fold process is done three times total, with 30-minute refrigeration breaks in between before chilling overnight. |
Note: while many baking
recipes insist on weighing out ingredients, which is more precise than using
volumes (cups, tablespoons, etc), from the graph you should get an idea for the
margins of error acceptable within a croissant dough recipe, so really the
precision of a scale is not necessary.
 |
Left: After an overnight chill, I rolled the dough thin, to ~1/4 inch thickness, and cut out about 3-inch diameter circles (I used a ramekin as a template and just used a knife, if you want to be precise you can buy a donut/biscuit cutter
). I also cut out a 1-inch diameter circle from the center. Center: Two cronuts deep frying. Right: Two finished cronuts, with flaky cross-section. |
Frying technique:
Nothing too special about the frying technique, I made the laminated dough,
proofed it for an hour and a half, and then tried frying it within a range of
temperatures from 375-350 F (typical temperatures used in donut and beignet
recipes), and stuck to frying single donuts at 365 F for 90 seconds for a
softer outside, 120 seconds for a crispier texture, which was what I was
looking for. After removing from the
oil, I dusted on some regular sugar while the exterior is still hot.
 |
| Left: I don’t have a piping bag with a thin enough opening, so I used one of those ketchup-looking squeeze bottles to fill the cronuts with beer pastry cream. Left-Center: A finished bronut filled with beer pastry cream, topped with chocolate shavings and more beer pastry cream. Right-Center: Bronut cross-section. Right: Don’t forget about those cronut holes! |
| Fillings: Since the original cronut had a lemon pastry cream that seemed maybe a bit too light, I decided to make two types of fillings: a lemon pastry cream like the original, except less sweet, and a beer pastry cream. The cronut is already very light and airy, so I thought that a heavier pastry cream would actually be a better complement. This, and the fact that my friend Yanran over at skinny bacon had coined the name “bronuts” made using beer the obvious choice. To make the beer pastry cream, I just used a standard pastry cream recipe I found online but substituted half the milk with a pale ale and 2 tbsp butter. For lemon pastry cream, just grate a lemon’s worth of zest into the simmering milk. |
After injecting the beer pastry cream into the cronut, I
topped it with some chocolate shavings, followed by another ring of pastry
cream aaaand boom – bronut complete.
Oh, and remember to save the cronut holes. They're good eats too!
Oh, and remember to save the cronut holes. They're good eats too!
