Salmon Quesadillas

2 garlic cloves, minced
1 teaspoon vegetable oil
1 (15 3/4 ounce) can salmon, drained, with skin removed
1 to 2 teaspoons dried basil
1/2 teaspoon pepper
1 tablespoon butter, softened
4 (8-inch) flour tortillas
2 cups shredded mozzarella cheese
Guacamole or salsa

Saut