In a 4-quart saucepan, heat olive oil over medium heat. Add the onion, jalapeno pepper, and garlic and cook stirring frequently, for 3 minutes. Stir in the beer and cook until the liquid is reduced by half. Stir in the cream, cream cheese, and processed cheese, whisking until melted and smooth.
Stir in crabmeat, lime juice, green onion, cilantro, and chili powder and simmer for 15 minutes. Add the salt, black pepper, cayenne, and cumin. Transfer the dip to a serving bowl and garnish with sliced jalapeno pepper, if desired. Serve hot with tortilla chips.
In a deep-fryer or heavy-bottomed pot, heat enough oil to come halfway up the sides of the pot, to 375 degrees F.
Cut the tortillas into triangles. Fry them, in batches, until golden, about 2 minutes. Remove the tortillas from the oil to paper towels to drain. Sprinkle with salt, to taste, and serve.