To a bowl, add egg, buttermilk and oil. Whisk until combined.
To the same bowl, add corn meal, flour, salt, garlic powder, sugar and baking powder. Using a spatula, fold the dry ingredients into the wet. Do not over mix.
Add in the minced jalapeño and cheddar cheese. Fold in with a spatula until well combined.
If you want to make the parchment paper liners, cut 5x5 squares. Using a glass push the parchment paper into each muffin well.
Preheat the oven to 400℉.
Line a muffin tin with parchment squares and using a 3 oz cookie scoop, scoop equal portions of batter into each well. Top with more shredded cheddar and a jalapeño slice.
Bake at 400℉ for 30-35 mins or until a knife comes out clean.