Start with your crust- Crush Oreos, I always use my Blendtec Twister Jar, but you could use a Ziplock and a rolling pin, crush the cookies. Melt the vegan butter in a medium-size bowl and then add the crushed cookies and stir. Take an 8x8 pan and spray cooking spray on it, then crush the cookie vegan butter mixture evenly on the bottom, set aside. Now make your chocolate pudding mixture. Take a medium saucepan. Mix the sugar, cocoa powder, salt, and cornstarch. Use a whisk and whisk it until combined. Then add half of the plant milk, stir until smooth, then add the rest of the plant milk and peanut butter. Cook on medium heat, you want it to simmer, stirring constantly for about 8 minutes until thickened. It will thicken up a lot off the heat, you basically want it to coat the spoon well. Now remove from heat and add your chocolate, and vanilla extract, stir. Now set aside until cool. While that is cooling make your peanut butter mixture. Put all ingredients into a bowl and mix with a hand mixer until smooth. Take this mixture and spread it on top of the cookie crust. Now take your cooled chocolate pudding and mix the other half of the coco whip, stir. Then smooth this over the peanut butter layer. Stick in the fridge until cooled and then serve. I always top mine with crushed cookies for decoration.