Step 1: 1. Add the butter, jalapeño, and garlic to a small saucepan set over medium heat. Cook, stirring occasionally, the jalapeño is tender about 2 minutes.
Step 2: 2. Next, add the milk to the saucepan and whisk the ingredients together. Let the milk heat over medium heat until warm. Be careful not to burn the milk.
Step 3: 3. Gradually add the cheeses to the warm milk, stirring constantly. Stir until the cheeses have melted.
Step 4: 4. Serve topped with additional jalapeño and fresh cilantro.