In a large skillet, melt butter over medium heat. Add chicken and sauté for 2-3 minutes. Add onion, jalapeno, garlic, and cumin. Sauté until vegetables are tender, another ~5 minutes. Add diced tomatoes & chilies.
Add cream cheese and milk. Cook until smooth. Add beer.
In a separate bowl, toss together Cheddar and Monterey Jack cheese with the flour. Slowly add in the cheese & flour mixture into the melted cream cheese mixture.