Preheat the oven to 375 degrees F (190 degrees C). Spray a standard 12-well muffin tin with cooking spray or line cups with paper liners.
In a large bowl, combine flour, cornmeal, brown sugar, baking powder, and salt.
In a small bowl, whisk milk, butter, hot honey, egg, lemon juice, and lemon zest; pour into dry ingredients, and stir until just combined. Gently fold in the blackberries, and spoon batter equally into the prepared muffin tin.
Bake in the preheated oven until golden brown, 20 to 25 minutes. A toothpick inserted near the center should come out clean. Allow to cool for 5 minutes, remove from the pan, and serve.
