Unroll breadstick dough, separating into strips. Working on a flat surface, coil one strip of dough around itself in a spiral pattern. Add second strip of dough to the end of the first strip, pinching ends to seal; continue coiling dough. Repeat procedure with remaining dough to make an 8-inch flat circle. Roll dough into a 13-inch circle; fit into a 9-inch quiche dish or pieplate coated with cooking spray. Fold edges under and flute; set aside.

Coat a nonstick skillet with cooking spray; add oil, and place over medium heat until hot. Add onion and garlic; saute 8 minutes or until lightly browned. Spread onion mixture in bottom of prepared crust; sprinkle with cheese. Arrange tomato slices over cheese; top with basil.

Combine milk and next four ingredients in the container of an electric blender; cover and process until smooth. Pour over tomatoes. Bake at 350#161#F for 45 minutes or until a knife inserted 1 inch from center comes out clean; let stand 10 minutes before serving.