Collect all the ingredients and preheat oven to 350 degrees
Beat 1 3/4 cups of sugar, butter, and vanilla in mixer at medium speed until well blended.
Add pumpkin puree and eggs (one at a time) and beat until combined.
In a small bowl, whisk together flour, baking powder, and salt.
Add flour mixture to sugar mixture and beat at low speed until well blended.
Combine the remaining 1/4 cup sugar and cinnamon in a small bowl.
Toss the chopped and peeled apples with 2 Tbsp of the cinnamon sugar.
Fold 3 cups of the chopped apples into the cake mixture. Set aside the remaining cup.
Pour batter into a well-greased Handi-Foil cake pan.
Add the remaining apples over the batter, evenly, and lightly sprinkle the rest of the cinnamon sugar on top of the batter.
Bake at 350 degrees for 1 hour or until cake slightly browns on top.
Cool on a wire rack, then carefully remove springform pan and serve.
Drizzle with caramel sauce, if desired.
