When a “bird’s nest” of thread appears, the likely culprit is your upper thread tension. If loops appear on the underside of the fabric, the upper thread tension may be too loose. If knots appear on top of the fabric, the upper tension may be too tight.
Clean-Eating Raspberry Oatmeal Cookies -- these skinny cookies don't taste healthy at all! You'll never need another oatmeal cookie recipe again! my edit: don't taste healthy because they really aren't. but they look tasty!