Here is my recipe for no bake cookies. I have been using it a lot recently because it is too hot to turn on the oven.
With just the two of us, I have been cutting the recipe in half and pressing it into an 8 x 8 pan.
Sometimes, I leave out the cocoa and press a handful of chocolate chips into the top while still warm. Today I used 1/2 vanilla and 1/2 almond extract. Substituting Nutella for the peanut butter would be delicious too.