In a large bowl, mix together the butter and granulated sugar with a hand mixer. Beat on medium speed until the mixture becomes light and fluffy.
1/2 cup unsalted butter, 2/3 cup granulated sugar
Add the eggs one at a time and beat on low speed. Scrape down the bowl using a silicone spatula between each addition. Add vanilla extract and mix well.
2 large eggs, 2 tsp vanilla extract
In a separate bowl, whisk together your dry ingredients. With your mixer on low speed, add half the dry ingredients and mix. Next, add the milk and sour cream and mix. Once combine slightly, add the second half of dry ingredients and mix until full combined.
1 1/2 cups all-purpose flour, 2 1/2 tsp baking powder, 1/2 tsp salt, 1/3 cup milk, 1/3 cup sour cream
Use a cookie scoop or large spoon to transfer half the batter into the prepared loaf pan. Spread into an even layer then top with half the cinnamon apples. Scoop the remaining half of the batter over the apples, using a silicone spatula to spread into an even layer. Top with half of the cinnamon sugar before sprinkling the remaining cinnamon apples and more cinnamon sugar to finish it off!
Bake until the cake is golden brown all over and a butter knife inserted into the center of the loaf comes out clean, 40 to 45 minutes. Let cool before removing from loaf pan.