1. Preheat oven to 350 degrees. Lightly butter and flour a 4 1/2-by-8 1/2-inch loaf pan. In a large bowl, using an electric mixer, beat butter and sugar on medium-high until very light and fluffy, 7 minutes. Scrape down bowl and beat 1 minute more. Add vanilla, then gradually add eggs, beating well and scraping down bowl as needed. With mixer on low, add salt, then gradually add flour and cornmeal, beating well to combine and scraping down bowl as needed. Gently toss berries with remaining 1 tablespoon flour. Fold into batter.

2. Transfer batter to pan and bake until a toothpick inserted in center of cake comes out with a few moist crumbs attached, 65 minutes. Let cool in pan on a wire rack, 1 hour. Remove cake from pan and let cool completely on rack before slicing.

3. To store, wrap in plastic and keep at room temperature, up to 3 days, or wrap in plastic and freeze for up to 3 weeks. (Thaw, wrapped, at room temperature.)