3/4 c unsalted butter, room temperature
1 c sugar
1/2 c unsweetened applesauce
3 egg yolks
1 3/4 c flour
1 1/2 tsp baking powder
1/4 tsp salt
2 tsp cinnamon
1 1/2 Tbs maple syrup
1 1/2 tsp vanilla
1/2 c milk

1 egg
2 Tbs milk
1 tsp cinnamon

For Maple Frosting:

2 sticks unsalted butter, softened
2 3/4 c confectioners' sugar
2 tsp milk
3/4 tsp maple extract