Heat butter and olive oil in heavy saucepan until butter melts. Add onion and cook until translucent. Add tomatoes and continue to cook until soft. Add jalapeño and V8 juice. Bring to boil and add stock and hot water.
Bring to simmer. Add cumin, paprika, chili powder, white pepper, and garlic. Cook, stirring occasionally. Add tomato paste and 1/4 cup cilantro. Cook, stirring occasionally.
Mix cornstarch with 1 Tbsp water. Stir into tomato mixture. Simmer until liquid is shiny, about 10 minutes.
Cut tortillas into 1 1/2-inch strips and deep-fry in hot oil. Remove and drain.
To serve: Distribute 1/2 cup avocado, 1 cup chicken breast, 1/8 cup chopped cilantro and half the tortilla strips among 6 bowls. Ladle hot soup over this garnish and top with the remaining avocado, chicken breast, chopped cilantro, and tortilla strips. Pass grated Cheddar on the side.Makes 6 Source: