Sopa De Aguacate (Avocado Soup)

Yield:	6 Servings
Categories:	Mexican, Soups

4	tb	Shortening
3		Medium-sized avocados, mashed
1	tb	Flour
1/4	c	Chopped onion
1/3	c	Cream
1/2	c	Tomatoes, peeled and drained
		Green food coloring
3		Tortillas (bought), or 3 slices of bread
		Salt and pepper
4	c	Stock