Proof your yeast with 1 teaspoon of cane sugar and ¼ cup of water heated to 105-115ºF. Wait until the mixture becomes foamy before using.
Whisk together 3 ⅔ cups of flour, 2 tablespoons of cane sugar, and 2 teaspoons of salt. Mix in 3 tablespoons of vegan butter cubed.
Place into the bowl of a stand mixer with a dough hook attachment and start on a low speed.
Slowly pour in the proofed yeast, then 1 cup of milk into the dough.
Increase the speed of the mixer and allow it to knead the dough for 5-6 minutes, until the dough pulls away from the bowl and is soft.
Turn the kneaded dough out onto a floured surface, shape it into a ball, cover and refrigerate for 30 minutes.
Remove the dough from the fridge. Roll out the dough to a 9 x 15-inch rectangle, cover, and refrigerate for 4 hours, up to overnight.
Beat 1 ½ cups vegan butter and 2 tablespoons flour in a stand mixer using a paddle attachment.
Place the vegan butter onto a piece of parchment paper and cover it with another sheet of parchment paper. Use a rolling pin to roll out the butter into a 6 x 11 rectangle.
Chill for 30 minutes.
Remove the vegan butter block and dough from the fridge. Place the butter in the center of the dough and fold the dough over the edges. Fold the dough into thirds.
Roll out the dough into a 9 x 15-inch rectangle. Fold the dough in thirds. Roll out the dough again into a 9 x 15-inch rectangle, and fold again into thirds.
Chill for 4 hours to allow the vegan butter to harden, then repeat the folding and rolling process two more times.
Chill the dough for 4 hours up to overnight.
Roll out the dough into a 9 x 15-inch rectangle.
Using a sharp knife or pizza cutter, slice the dough in half lengthwise.
Cut each half of the dough into fourths. Cut each resulting rectangle in half diagonally to create triangles.
Stretch each triangle a bit. Then create a 1-inch notch at the base of the triangle. Roll the triangles up into crescents starting from the notched base of the triangle.
Refrigerate for 60 minutes.
Preheat the oven to 400ºF.
Using ¼ cup vegan milk, glaze the exterior of each croissant.
Bake for 18-20 minutes until golden brown. Allow the croissants to cool.
Slice two avocados into thin wedges and cut 8 oz of roasted red pepper into strips.
Pat the roasted red pepper to remove any excess liquid with paper towels.
Wash and dry the spinach.
Slice the croissants in half. Spread the vegan cream cheese on both sides. Add a layer of spinach, then a layer of roasted red pepper, and finally, a few slices of avocado.
Serve immediately.