Preheat oven to 325°. Spray an 8×4-inch metal loaf pan with baking spray with flour.
In a large bowl, beat butter, Parmesan, and sugar with a mixer at medium speed until creamy, about 2 minutes, stopping to scrape sides of bowl. Add eggs, one at a time, beating well after each addition.
In a medium bowl, whisk together flour, cornmeal, rosemary, salt, baking powder, and pepper. With mixer on low speed, gradually add flour mixture to butter mixture alternately with milk, beginning and ending with flour mixture, beating just until combined after each addition.
In a small bowl, whisk together ½ cup batter and pepper jelly. Spoon half of plain batter into prepared pan. Drop pepper jelly mixture over plain batter in spoonfuls. Top with remaining plain batter; swirl together with a knife. Tap pan on counter a few times to level out batter and release any air bubbles.
Bake until a wooden pick inserted in center comes out clean, about 50 minutes. Let cool in pan for 15 minutes. Remove from pan, and let cool completely on a wire rack.
Recipe by Taste of the South at https://tasteofthesouthmagazine.com/savory-pound-cake/