Walnut Praline *extra time required to toast and cool the walnuts
Preheat oven to 350º F. Oven rack in middle position.
EXTRA TIME REQUIRED for walnuts to toast and cool (can be done several days in advance)Toast the walnuts in a single layer on the baking sheet for 10 - 12 minutes until toasty and golden. Transfer to a bowl to cool.
Prepare the baking sheet with a parchment paper.
Put the sugar in a medium-sized, heavy-bottom saucepan. Stir in the water and shake to level the sugar.
Cook without stirring over medium-high heat until the caramel turns amber (about 8-12 minutes) ~350º F on a candy thermometer. *The time will vary depending on your pan and stove setting. **After the caramel starts to liquify and turn amber, I take the pan off the heat and swirl the liquid in the pan several times.
NOTE: The original recipe calls for 383º F on an instant read thermometer. I don't have an instant read and on a standard candy thermometer that made the caramel too dark for my taste.
Take the pan off the heat and immediately stir in the toasted walnuts using a silicone spatula. Dump onto prepared baking sheet, spreading it evenly into a single layer. Let cool completely.
Making the Dough
Sift the flour and baking powder.
Using a stand (or hand) mixer, beat the butter and sugar on medium-high speed until light and fluffy (~3 minutes).
Add the aquafaba and vanilla and beat until blended, scraping down the sides of he bowl as needed. It may look a little curdled (separated) but not to worry.
Add the sifted dry ingredients and mix on slow speed just until incorporated.
Remove ¾ cup (195 grams) of the dough and set aside to make a blanket for the log.
Chop the cooled praline walnuts into bite-size pieces. Stir them into the dough in the bowl.
Shaping the Biscotti Log
Place the dough on the prepared baking sheet. With damp hands, shape the dough into a log ~3 x 10". Warning: the praline shards can be sharp so be careful when handling.
Lightly roll and pat the reserve dough into a blanket to cover the top and sides of the log. Moisten hands and pat and patch the dough so all praline pieces are covered.
Baking the Biscotti (first bake)
Place log into oven and bake for ~35 minutes until the top and sides of the log are golden. Remove from oven and let cool for 30 minutes.
Reduce oven temp to 300º F.
Place the cooled log on a cutting board and using a sharp serrated knife cut into ½ - ¾" thick slices.
Place back on the baking sheet and do a second bake for 25-30 minutes (flip ½ way). The longer the second bake, the more dry, crunchy, hard the cookies become.
OPTIONAL - top each biscuit with chocolate drizzles and a few flakes of finishing salt.
Notes
Aquafaba - vegan egg replacement that acts like egg white adding structure and protein to recipe. Aquafaba is the leftover liquid in canned beans (typically chickpeas).Store aquafaba in an air-tight container in the fridge for a week. For a longer storage, pour into ice cube trays. Once frozen, pop them out and place in a freezer bag to be used over the next several months.Toasted Walnuts - walnuts can be toasted and stored in an air-tight container in the fridge a week or so before time.Candy Thermometer - I used an old fashion candy thermometer so adjusted the temperature of the praline. The original recipe cooked to 383º F and used an instant read thermometer. That higher temperature was burning my caramel.Toppings - the toppings are optional, but if you want to elevate your biscotti's decadence level, drizzle some salted caramel and/or melted chocolate on the biscotti with a pinch of Maldon salt flakes before serving.