Apple Walnut Sticky Buns
Preheat the oven to 400 degrees F. Generously butter a 12-count muffin tin.
Divide the apple mixture evenly into the muffin tin. Put 12 cinnamon buns, cinnamon side down, on top of the apple mixture. Put the muffin tin on a baking sheet and bake until the tops are golden brown, about 8 to 10 minutes. (Bake off remaining 4 buns for Round 2 Recipe Cinnamon Roll French Toast.)
Remove the muffin tin from the oven and allow to cool for 5 minutes. Put a clean baking sheet on top of the muffin tin and flip to remove the sticky buns.
In a small bowl, combine 1 container of the vanilla frosting (save the other for Round 2 Cinnamon Roll French Toast) with the pumpkin pie spice and 1 to 2 teaspoons of water. Mix until very thick and of pourable consistency. Drizzle over buns and serve.