Preheat oven to 350 degrees F. Thoroughly grease each cavity of the mini bundt pan, making sure to coat every curve and ridge to prevent sticking.
In a medium bowl, whisk together 1 1/2 cups all-purpose flour, 1 teaspoon baking soda, 1/2 teaspoon baking powder, 1/2 teaspoon salt, 1 1/2 teaspoons ground cinnamon, 1/4 teaspoon freshly ground nutmeg, and 1/4 teaspoon freshly cracked black pepper.
In a separate large bowl, whisk 2 large eggs, room temperature with 3/4 cup granulated sugar and 1/2 cup light brown sugar, packed until slightly thickened and smooth. Stream in 1/2 cup neutral oil such as canola or vegetable while whisking, then stir in 1/3 cup sour cream and 1 teaspoon pure vanilla extract.
Fold the dry ingredients into the wet mixture just until combined. Stir in 1 1/2 cups finely grated carrots, lightly packed (about 2 large carrots), 1/3 cup well-drained, crushed pineapple (measure after draining), and 1/2 cup finely chopped pecans (optional), lightly toasted, if using. The batter will be thick but spoonable.
Divide the batter evenly among the prepared mini bundt cavities, filling each about 3/4 full. Do not fill more than ¾ full. (See notes for how to use leftover batter.) Gently tap the pan on the counter to release air pockets.
Bake for 20–24 minutes (for 1-cup cavities), or until a toothpick inserted into the center comes out with a few moist crumbs but no wet batter. Internal temperature should reach about 200 degrees F in the center.
Cool in the pan for 10 minutes before carefully inverting onto a wire rack to cool completely.
For the glaze
Beat 4 ounces full-fat brick-style cream cheese, softened and 2 tablespoons unsalted butter, softened until smooth and creamy. Add 1 cup confectioners sugar and 1/2 teaspoon pure vanilla extract, then mix in milk one tablespoon at a time until the glaze is thick but pourable. Add a pinch of salt to balance the sweetness.
Spoon or drizzle generously over cooled cakes. NOTE: When spooning the glaze over the cakes, start in the center and gently guide it toward the outer edge to encourage natural drips. Add a bit more glaze where you want longer cascades and less where you prefer shorter ones. A mix of drip lengths creates a more dynamic, bakery-style finish that looks especially beautiful when served.
Notes
To toast pecans, spread them on a baking sheet and bake at 350 degrees F for 6–8 minutes until fragrant. Let them cool completely before folding into the batter. Toasting deepens flavor and prevents that slightly raw, waxy nut texture.
To keep carrot cake moist, avoid overbaking and measure flour properly by spooning and leveling.
Pineapple in carrot cake is technically optional, but the small amount here adds moisture and subtle sweetness without making the cake dense.
To avoid sticking in your mini bundt cake pan, the key is thorough greasing and allowing a short cooling period before turning them out. For a professional pan release, make “cake goop” by combining equal parts vegetable shortening, neutral oil, and all-purpose flour until smooth. Use a pastry brush to apply a thin, even layer to every ridge and curve of your pan. Be especially thorough around the center post and tight details.