Preheat oven to 350°F (175°C). Grease and flour a bundt pan thoroughly.
- In a medium bowl, whisk together flour, baking soda, baking powder, salt, cinnamon, and nutmeg.
- In a large bowl, whisk together oil, granulated sugar, and brown sugar until smooth.
- Add eggs one at a time, mixing well after each. Stir in vanilla and sour cream.
- Gradually add dry ingredients to the wet mixture, mixing until just combined.
- Fold in the diced apples.
- Pour the batter into the prepared bundt pan and smooth the top.
- Bake for 50–60 minutes, or until a toothpick inserted in the center comes out clean.
- Cool in pan for 15 minutes, then invert onto a wire rack and cool completely.
- To make the glaze: In a saucepan over medium heat, melt the butter. Stir in brown sugar and cream and bring to a gentle boil. Simmer for 2–3 minutes, then remove from heat and stir in vanilla and salt.
- Let the glaze cool slightly before drizzling over the cooled cake.