Preheat oven to 325°F and generously grease a 10-12 cup bundt pan with butter and flour or baking spray with flour.
Whisk together dry ingredients: In a large bowl, combine 3 cups flour, cinnamon, baking soda, 1/2 teaspoon salt, and nutmeg. Set aside.
Beat eggs and sugars: In another bowl, beat 4 eggs until light and foamy (about 2 minutes). Add granulated sugar and 1/2 cup brown sugar, mixing until well combined.
Add wet ingredients: Slowly drizzle in vegetable oil while mixing, then stir in 2 teaspoons vanilla extract.
Combine wet and dry: Gradually add flour mixture to wet ingredients, mixing just until combined. Don't overmix - a few lumps are fine.
Prepare apples and pecans: Toss chopped apples and toasted pecans with 2 tablespoons of the flour mixture to coat, then fold into batter.
Bake: Pour batter into prepared bundt pan and smooth the top. Bake for 75-90 minutes until a toothpick inserted near the center comes out clean.
Cool cake: Let cool in pan for 15 minutes, then invert onto a wire rack to cool completely.
Make caramel glaze: In a heavy-bottomed saucepan, melt butter over medium heat. Add 1 cup brown sugar, heavy cream, and pinch of salt. Stir constantly until mixture comes to a boil.
Finish glaze: Boil for 2 minutes, stirring constantly. Remove from heat and stir in 1 teaspoon vanilla. Let cool until warm but not hot.
Glaze cake: Pour warm caramel glaze over cooled cake, allowing it to drip down the sides. Let glaze set before serving.