Prep the Oven and Pan: Preheat your oven to 350°F (175°C). Grease a 9x13-inch baking pan or a large Bundt pan to prevent sticking.
Mix Dry Ingredients: In a medium bowl, whisk together 3 cups of flour, 1 teaspoon of baking soda, 2 teaspoons of ground cinnamon, ½ teaspoon of ground nutmeg, and ½ teaspoon of salt. Set aside.
Combine Wet Ingredients: In a large mixing bowl, combine 1 ½ cups of vegetable oil, 1 cup of sugar, ½ cup of packed brown sugar, and 2 teaspoons of vanilla extract. Stir until smooth and well mixed.
Add Eggs: Crack in 3 eggs, one at a time, mixing well after each addition until the batter is smooth and fluffy.
Incorporate Dry Ingredients: Gradually add the dry ingredients into the wet mixture, stirring gently until just combined and no dry streaks remain.
Fold in Apples: Gently fold in 5 medium peeled and cubed apples. Mix until the apples are evenly distributed throughout the batter. I usually use about 3 Honeycrisp apples and 2 Granny Smith apples.
Pour and Bake: Pour the batter into the prepared pan and spread it out evenly. Bake for 50–60 minutes, or until a toothpick inserted in the center comes out clean.
Prepare the Warm Glaze: When the cake is almost finished baking, melt ⅓ cup butter in a small saucepan over medium heat. Add ⅓ cup packed brown sugar, ¼ cup sugar, and ⅓ cup heavy cream, stirring until smooth. Let the glaze come to a gentle simmer, then cook for an additional 2–3 minutes until slightly thickened. Remove from heat and stir in ½ teaspoon vanilla extract.
Glaze the Cake: While the cake is still warm, pour the glaze over the top, letting it soak in for extra flavor and moistness.
Cool and Serve: Allow the cake to cool slightly before slicing. Enjoy warm for the best flavor!