To roast the poblano pepper, place it directly on your gas burner and cook, turning occasionally, until the skin is completely blackened on all sides. (If you don’t have a gas burner, you can use your broiler.) Place the pepper in a bowl, cover with plastic wrap and allow to steam for about 15 minutes. Remove the skin and seeds from the pepper, resisting the urge to rinse it, and cut it into medium dice.

Heat a 9-inch cast iron skillet or cazuela over medium heat and add the olive oil. Sauté the mushrooms and onions, stirring occasionally, until lightly caramelized, about 5 minutes. Add the garlic and cook an additional minute.

While the mushrooms and onions are cooking, toss the cheese with the cornstarch in a bowl.

Add the beer and tequila to the mushroom-onion mixture, and cook until it begins to simmer. Gradually add the cheese, and mix until melted and smooth. Stir in the diced pepper and the cilantro.

Serve hot with tortilla chips.