Brown garlic, onion and tomato with margarine in a stock pot.
Add tomato sauce, vegetable stock, chiles, pepper, sugar and taco sauce. Simmer for 1 hour.
To assemble soup put a handful of tortilla strips in a large open soup bowl, top with 4 or 5 thin avacado wedges, chopped fresh onion and Mexican ranch style crumbly cheese (or Cheddar). Ladle in hot soup and top with a spoonful of sour cream.