Preheat the oven to 350 (F).
In a medium bowl, whisk together 2 cups flour, 1/4 teaspoon baking powder, 3/4 teaspoon baking soda, 1/4 teaspoon cinnamon, and a dash of salt. Set aside.
In the bowl of a freestanding mixer with a paddle attachment, cream together 1/2 cup butter and 1 1/2 cups sugar. Add 2 eggs one at a time, beating well after each addition.
Add 1/4 cup sour cream, beating until just incorporated, and then add the flour mixture (from the second step) and beat until just incorporated.
Use a rubber spatula to mix in 3 bananas, 1/3 cup caramel syrup, and 1/2 cup toffee chips. Stir until just incorporated. Pour the batter into greased loaf pan and bake for approximately 60 minutes, or until a toothpick inserted into the center comes out clean.