Vanilla Twinkie Bundt Cake with Raspberries

Ingredients 
Cake ~

• 3 cups cake flour
• 1 tablespoon baking powder
• ¾ teaspoon salt
• 6 tablespoons unsalted butter, at room temperature
• 1 tablespoon vanilla bean paste
• 1½ cups granulated sugar
• ½ cup vegetable oil
• 3 large eggs plus 4 large egg yolks, at room temperature
• 1 cup buttermilk, at room temperature
• 2 cups fresh or frozen raspberries

Filling ~

• 2 (7.5 ounce) jars marshmallow creme
• 1 cup (2 sticks) unsalted butter, at room temperature
• 2 teaspoons pure vanilla bean oaste
• Confectioners' sugar, for dusting (optional)

Preparation
Cake ~

1. Position rack in the lower third of the oven and preheat oven to 325°F. 
2. Coat a 12-cup Bundt pan with nonstick cooking spray and dust it lightly with flour.
3. Sift together the flour, baking powder, and salt into a large bowl.
4. In the bowl of a stand mixer fitted with the paddle attachment, beat butter and vanilla extract on medium speed until smooth and creamy. 
5. Add sugar and beat until evenly mixed, about 1 minute. 
6. Slowly pour in oil. Beat until light and fluffy, about 2 minutes. 
7. Add eggs and egg yolks, 1 at a time, beating thoroughly after each addition.
8. Reduce mixer speed to low and add flour mixture and buttermilk in three alternating additions, ending with the buttermilk, and continue to mix on low speed until the batter is smooth and no lumps remain. 
9. Turn off mixer and fold batter several times by hand to ensure everything is well incorporated.
10. Add raspberries and gently fold until incorporated, and then add to prepared pan.
11. Bake for 60 to 70 minutes, until the cake is golden, the top springs back when lightly pressed, and a cake tester inserted into the center comes out clean. 
12. Place pan on a wire rack and let cool completely, about 2 hours.

Filling ~

1. In the bowl of a stand mixer, beat together marshmallow creme, vanilla, and butter until smooth. Transfer to a pastry bag fitted with a large round tip.
2. With the cake still in the pan, use a paring knife or apple corer to cut 6 or 7 deep holes into the bottom of the cake, each about 3/4 inch in diameter; be careful not to cut through top of cake. Discard (i.e., nibble) cake scraps. With your fingers, gently burrow a horizontal tunnel around the center of the cake, connecting the vertical holes.
3. Insert the tip of the pastry bag into each hold and squeeze in filling, tilting pastry bag back and forth as you work to encourage filling into the horizontal tunnel through the cake. When cake is filled, use a spatula to scrape away excess filling from the bottom of the cake. Quickly and carefully invert cake onto serving platter. Dust with confectioners' sugar, if desired, and serve.