1. Preheat oven to 350°.
2. To prepare muffins, weigh or lightly spoon flour into dry measuring cups; level with a knife. Combine flour, cornmeal, baking soda, baking powder, and 1/4 teaspoon salt in a medium bowl, stirring well with a whisk. Combine buttermilk, butter, and 1 egg, stirring well. Add buttermilk mixture to flour mixture, stirring just until combined. Stir in cheese and jalapeño. Spoon batter into 12 muffin cups coated with cooking spray. Bake at 350° for 17 minutes or until a wooden pick comes out clean. Cool 5 minutes in pan on a wire rack. Remove muffins from pan; cool on a wire rack. Cut muffins in half crosswise.
3. To prepare chicken, place panko in a shallow dish. Combine fat-free milk and 1 egg in a shallow dish, stirring well. Split each chicken breast in half lengthwise to form 2 cutlets; cut each piece in half, crosswise, to form 12 pieces. Heat a large skillet over medium-high heat. Add 1 tablespoon oil to pan; swirl to coat. Dip chicken in egg mixture; dredge in panko. Coat panko lightly with cooking spray. Add 6 chicken cutlets to pan; cook 3 minutes on each side or until golden and done. Repeat procedure with remaining 1 tablespoon oil, remaining 6 chicken cutlets, and cooking spray.
4. To prepare additional ingredients, combine avocado and lime juice; mash to desired consistency. Stir in bacon. Place 2 muffin bottom halves on each of 6 plates. Divide avocado mixture evenly among muffins; top each slider with 1 chicken cutlet and 1 tomato slice. Sprinkle tomato evenly with 1/4 teaspoon salt and black pepper; top with muffin tops.