Preheat oven to 400°F. Prepare 9-cup jumbo muffin pan with vegetable pan spray.
In large bowl, whisk together flour, cornmeal, sugar, baking powder, baking soda and salt. Stir in jalapenos and 1 cup cheese.
In medium bowl, combine butter, buttermilk and eggs; whisk until combined. Add buttermilk mixture to cornmeal mixture and mix until just combined. Divide mixture evenly into prepared pans. Sprinkle evenly with remaining 1/2 cup cheese.
Bake 23-25 minutes or until golden brown around edges. Cool in pan on cooling grid 5 minutes.