Why It Works
- Cream of tartar helps to stabilize the aquafaba emulsion, helping to produce a voluminous foam that doesn't collapse.
- Cream of tartar lowers the pH of the meringue, preventing it from browning during heating, which yields a satiny white frosting.
- Heating the frosting helps get rid of some of the bean aroma from the aquafaba, while bold flavorings help cover up what remains.
For people who avoid eggs due to allergies or dietary reasons, eating meringue cookies is completely out of the question. A classic meringue’s light, pillowy texture is made possible because of the unique properties of egg whites; when egg whites are whipped at a high speed with sugar, their proteins change shape (a process called protein denaturation) and trap air, forming a stable foam. However, an eggless “meringue” can be made using aquafaba, the cooking liquid of beans and legumes like chickpeas.
Aquafaba contains proteins (albumin and globulins, the type of water-soluble proteins seen in egg whites) and saponins (molecules that behave like soap and produce foams), and, when whipped with sugar, they produce a surprisingly convincing meringue substitute. With that in mind, I wanted to try to figure out the optimal cooking conditions to produce delicious vegan meringue cookies that are shiny, white, and pillowy, so I set up a bunch of different experiments, which you can read about by clicking on the link below.
In the end, I found that it's best to use aquafaba from cans of chickpeas that have been cooked with kombu because it contains carrageenan, a carbohydrate that can form gels and is often used as an emulsifier in products like evaporated milk. I also found the addition of cream of tartar, an acid, to the meringue mixture both produces a more stable foam and cookies that have very little browning, as the acid inhibits caramelization and Maillard reactions. Finally, I found that aquafaba meringue needs a strong aromatic flavoring component, as adding even a large amount of vanilla extract did little to mask the beany smell. Ingredients with more robust aromas, however, like ground green cardamom or coffee, do a fantastic job of covering up the bean aroma.
Just like an egg-based meringue, the aquafaba meringue needs to be baked at a low temperature of 200°F/95°C for at least 2 hours. The lower temperature reduces the risk of browning and helps the meringue slowly dehydrate and hold its structure. Resist the urge to open the oven door for at least 1 hour, as the meringue might still be delicate and can deflate (my current oven is a bit of a nightmare and the door slams back pretty hard).
Aquafaba meringue cookies are one of the best ways to use what might otherwise end up as food waste. All it takes is sugar, canned chickpea liquid (if you can find the ones that are cooked with kombu, even better), cream of tartar, and an aromatic ingredient for a vegan treat that’s just as shiny, white, and pillowy as meringues made with egg whites.
- 1/2 cup (120ml; 130g) aquafaba (see note)
- 1/2 cup (100g) superfine sugar
- 1/4 teaspoon ground green cardamom
- 1/4 teaspoon cream of tartar
Preheat oven to 200°F (95°C) and set oven racks to middle positions; line two rimmed baking sheets with parchment paper. In the bowl of a stand mixer fitted with the whisk, combine aquafaba, sugar, cardamom, and cream of tartar.
Whisk at medium speed for 1 minute, then increase speed to high and whisk, stopping once or twice to scrape sides and bottom to ensure sugar is fully incorporated, until meringue reaches satiny, stiff white peaks, about 10 minutes (see note).
Using a 1-tablespoon measuring spoon or a pastry bag fitted with the 1/2-inch (1.27cm) round tip, spoon or pipe the meringue into 2-inch (5cm) circles spaced 1 inch (2.5cm) apart on the prepared baking sheets.
Bake the meringues without opening the oven door for 1 hour. Swap the baking sheet positions and rotate them front to back, then bake until the meringues are white in color and dry and firm to the touch, about 30 minutes longer (note that baking times can vary, and it may take up to 2 hours total baking time). Remove the sheets from the oven and let the meringues cool on the baking sheets.
Serve, or transfer the cooled meringues to an airtight container and store for up to 3 days.
Aquafaba is the cooking liquid collected from beans (in this case chickpeas). Canned liquid is best for reliable and consistent results, but you can also use the liquid from beans cooked at home. Please note that while home-cooked chickpeas can produce aquafaba that works, you may end up with varying results depending on how much water was used to cook the beans and how they were cooked. One 15-ounce (425g) can of chickpeas gives about 2/3 cup (160g) aquafaba.
The time taken to form stiff peaks tends to vary depending on the aquafaba source and viscosity. For this reason, it is better to use visual cues as an endpoint. Stiff peaks can appear anywhere between about 4 mins to 12 minutes.
Make-Ahead and Storage
The baked meringues can be stored in an airtight container at room temperature for up to 3 days. Depending on the ambient humidity in your room, the meringues can absorb moisture from air. You can reheat them at 150°F/65.5°C for 10 minutes to get rid of the absorbed moisture before serving. You can also drop a packet of food-safe silica gel beads along with the meringues in the airtight container; it will help prevent the cookies from absorbing too much moisture.