Found this recipe online and was thinking of giving it a go 

Healthy Birthday Cake for Chickens
Ingredients:
1/2 cup flour ā we used einkorn flour because itās healthier
1/2 cup water
1/2 cup creamy peanut butter
1 tsp aluminum free baking powder ā where to find
1 apple, diced into small pieces
6 strawberries, chopped into small pieces
1/4 cup raisins
coconut oil for greasing cake molds or baking sheet
toppings of your choice: homemade whipped cream, homemade yogurt, dried fruits, seeds, chopped fruit, meal worms, chicken feed, etc
Directions:
Preheat oven to 350° F
Grease cake molds, or a baking sheet with coconut oil (we used both in the recipe to show you how to do both)
Combine flour, water, peanut butter, and baking powder in a bowl. Stir until combined
Toss in apples, strawberries, and raisins
Pour batter into molds or form into a round shape on the baking sheet (this will make 2 round cakes)
Bake for 20 minutes
make sure your chickens check to see if they are done or not!
Transfer to a fancy plate to serve to your chicken
Top with toppings of your choice
Serve to your favorite birthday chickens
Healthy Birthday Cake for Chickens
Ingredients:
1/2 cup flour ā we used einkorn flour because itās healthier
1/2 cup water
1/2 cup creamy peanut butter
1 tsp aluminum free baking powder ā where to find
1 apple, diced into small pieces
6 strawberries, chopped into small pieces
1/4 cup raisins
coconut oil for greasing cake molds or baking sheet
toppings of your choice: homemade whipped cream, homemade yogurt, dried fruits, seeds, chopped fruit, meal worms, chicken feed, etc
Directions:
Preheat oven to 350° F
Grease cake molds, or a baking sheet with coconut oil (we used both in the recipe to show you how to do both)
Combine flour, water, peanut butter, and baking powder in a bowl. Stir until combined
Toss in apples, strawberries, and raisins
Pour batter into molds or form into a round shape on the baking sheet (this will make 2 round cakes)
Bake for 20 minutes
make sure your chickens check to see if they are done or not!
Transfer to a fancy plate to serve to your chicken
Top with toppings of your choice
Serve to your favorite birthday chickens
Hens go broody when you don’t want them to… and won’t go broody when you do. 