1 cup buttermilk

1/3 cup orange juice

2 tsp orange zest

1 1/3 cups yellow cornmeal (about 7 ounces)

2 large eggs

1 teaspoon Vain vanilla extract

1 1/3 cups all-purpose flour, plus 1 tablespoon

1 1/3 cups yellow cornmeal (about 7 ounces)

3/4 cup sugar

1 tablespoon baking powder

3/4 teaspoon fine salt

1 1/2 sticks chilled unsalted butter, cut into 1/2-inch cubes

1 1/2 cups frozen blueberries (7 to 8 ounces; do not thaw)

Position an oven rack in the center of the oven and preheat to 400 degrees F. Line a standard 12-cup muffin pan with paper liners.

In a large bowl, whisk the buttermilk, orange juice, orange zest, eggs and vanilla to blend. Combine 1 1/3 cups of the flour, the cornmeal, sugar, baking powder and salt in a processor, about 30 seconds. Drop in the cold butter cubes. Using on/off turns, blend until the butter is cut in finely and the mixture resembles a coarse meal, stopping occasionally to check the size of the butter pieces, (they should be the size of rice kernels). Pour the dry ingredients over the buttermilk mixture. Using a thin, flexible spatula and a few quick strokes, fold the batter together, turning the bowl as you fold.

In a medium bowl, combine the remaining 1 tablespoon flour and the frozen blueberries. Toss to coat the berries. Scatter the berries over the batter and fold in.

Using a rounded 1/3 cup of batter for each muffin, fill the paper liners, mounding the batter in the center. Use a knife tip or spoon to reposition at least 1 berry so it is showing on top.

Bake the muffins until puffed and browning at edges, and a tester inserted into the center comes out clean, 20 to 25 minutes. Let the muffins stand 5 to 10 minutes.  Lift the muffins out onto a rack and cool.