In a medium bowl, mix the flour, cornstarch, baking powder, and salt. Set aside.

Beat the softened vegan butter and sugar together in a stand mixer or using an electric handheld mixer for 2 minutes or until it comes together. Scrape the sides of the bowl and beat again for another minute, until light and fluffy. Add in the plant based milk and extracts and mix until combined.

Slowly combine the dry with the wet and beat until a dough has formed – about 2-3 minutes of mixing. 

Divide the dough into 6 balls as follows: 2 balls that are 250 grams each. 2 balls that are 170 grams each. 2 balls that are 100 grams each. Using gloves, color the dough: add gel food coloring (start with a little bit and add more as needed). Color the 250 gram balls: one red and one orange. Color the 170g balls: one yellow and one green. Color the 100g balls: one blue and one purple. I work the gel coloring into the dough with my hands which can take a couple of minute per color.

Roll the purple dough into a 12 inch long log (see video for reference) and set aside. Roll out the blue dough so that it's as long as the purple log but flat so that it can wrap around the purple log. I use the log as a reference so that the blue dough is *just* big enough to wrap around. Place the purple log in the center of the blue dough and wrap the blue around the purple. Pinch the seems to seal them. Repeat with the remaining colors until all of the dough is used up in this order: purple, blue, green, yellow, orange, red.

Wrap the cookie dough log tightly with plastic wrap and chill for 1 hour or even overnight.

Pre-heat the oven to 350 degrees and line a large baking sheet with parchment paper.

Once ready to bake, slice the dough into 1/3 inch thick coins and then slice those in half to make 2 rainbows. Repeat with all of the dough and place the rainbows on the prepared baking sheet. Chill the dough until it's ready to go in the oven.

Bake for 11-13 minutes or until the dough is just starting to look set. Mine are always a little shiny on the tops when they first come out, as if they aren't quite done yet, but they'll be perfect! The bottoms of the rainbows will most likely puff up a bit so I used a butchers knife or pastry cutter to lightly and gently flatten the bottoms back. Let cool and ENJOY!