Prepare cake mix according to package directions. Divide batter in half and color one with red food coloring and one with green food coloring. Bake in 2 round pans according to package directions, let cool completely. 

Prepare sugar cookie mix according to the "drop cookie" recipe directions on the package. I found this is a very stiff dough, and it takes a while to come together, but it will. Divide dough in half and shape into a ball with your hands. Make a divot in the center of each dough ball. Add red food coloring. Put on gloves and knead the dough until it's red. Repeat with the green dough ball. 

Use a tablespoon scoop to scoop dough onto the baking sheet and bake according to package directions. Let cool completely. 

Add milk to a bowl and whisk in pudding. Whisk until smooth. Refrigerate for 5 minutes until firm. 

Cut 2 red and 2 green cookies in half. Set aside. 

Break apart 10 red cookies and 10 green cookies and place in a bowl. 

Slice cake into 1" cubes. Layer the cake, alternating colors, in the bottom of a trifle bowl. Top with half of the pudding and half of the whipped topping. Sprinkle with half of the crumbled cookies. Repeat layers, ending with about 1/4 of the remaining whipped topping on top. Place the remaining whipped topping in a resealable sandwich bag and snip the tip. 

Use the whipped topping in the bag to pipe the whipped topping onto the top of the trifle. Place 1 half cookie into each dollop. 

Serve immediately or refrigerate, covered until ready to serve.