Melt the butter over low to medium low heat. When the butter is melted, briefly saute the jalapenos and garlic until just fragrant. No more than 2 minutes.

When the garlic and pepper is just becoming fragrant, take the pan off the heat. Stir in half and half. Once the half and half and garlic and peppers are combined, returned to the heat and start melting in the cheddar and mascarpone cheese. Top with remaining cheddar cheese and broil for 1 minute or until the cheese melts. Serve and enjoy!