PREHEAT oven to 350°F (180°C).
MIX 1 cup (250 mL) sour cream, cooked chicken, 1 cup (250 mL) cheese, 1/4 cup (50 mL) salsa, cilantro and cumin.
SPOON about 1/3 cup of the chicken mixture into each tortilla; roll up.
PLACE seam-side down in lightly greased 13x9 inch (3.5 L) baking dish; top with remaining salsa.
COVER and bake for 30 minutes; sprinkle with remaining cheese and bake until cheese has melted.
TOP with lettuce and tomato; serve with remaining sour cream.