Place ¾ cup buttermilk in a shallow bowl. In a separate bowl, combine cornmeal, 1 teaspoon salt, and ¼ teaspoon pepper.
Dip chicken in the buttermilk (letting any excess drip off), then the cornmeal, pressing gently to help it adhere.
Heat 3 tablespoons oil in a skillet over medium-high heat. Cook half the chicken until golden and cooked through, 2 to 3 minutes per side. Transfer to a plate.
Wipe out the skillet. Repeat with remaining oil and chicken.
In a small bowl, whisk together sour cream, honey, remaining ¼ cup of buttermilk, and ¼ teaspoon salt.
In a large bowl, toss lettuce and bell pepper with the dressing. Serve with the chicken.