Preheat the oven to 400°F. Lightly grease a 12-cup muffin pan or line it with parchment liners. Set aside while preparing the batter.
In a large bowl, whisk together the cornmeal, flour, baking powder, baking soda, salt, sugar, and smoked paprika until evenly combined.
In another bowl, whisk the eggs, buttermilk, and melted butter until smooth. Make sure the butter has cooled slightly before mixing with the eggs.
Pour the wet ingredients into the dry ingredients and gently stir until just combined. Avoid overmixing, as it can make the muffins dense.
Fold in the shredded cheddar cheese, corn kernels, jalapeños, onion, and cilantro until evenly distributed throughout the batter.
Divide the batter evenly among the muffin cups, filling each about three-quarters full. Bake for 20–25 minutes, until the tops are golden and a toothpick inserted in the center comes out clean.
Let the muffins cool in the pan for 5 minutes, then transfer them to a wire rack. Serve warm with butter, honey, or your favorite savory dishes.
