Preheat oven to 500 degrees F.
Put the oiled corn on a baking sheet and sprinkle it with salt and pepper. Put the oiled tomatoes on another baking sheet and roast them both for 10 to 12 minutes until the tomato skin blisters and the corn is lightly browned. In a medium skillet, grill the red pepper over medium-high heat until it is black on each side. Put the tomatoes and the pepper in the refrigerator, and peel them when they have cooled.
Heat the butter in a large pot over medium heat and add the onion and garlic and saute. Add the flour and cook for 2 to 3 minutes. Add the chicken stock, roasted corn, peeled tomatoes, half-and-half, and 1 1/4 cups of the tortilla chip pieces and mix well. Pour this mixture in a food processor or blender* and puree until smooth. Strain the chowder, and then season it with cumin, chili powder, salt, and pepper, to taste. Peel and dice the roasted red pepper. Serve the soup topped with diced avocado, red pepper, and the remaining tortilla chip pieces. Serve immediately.
This recipe was provided by a chef, restaurant or culinary professional. It has not been tested for home use.
When blending hot liquid, first let it cool for five minutes or so, then transfer it to a blender, filling only halfway. Put the lid on, leaving one corner open. Cover the lid with a kitchen towel to catch splatters, and pulse until smooth.