Cook pasta shells according to package directions, adding lots of salt to the water. Drain and set aside.
Brown two cloves of minced garlic in medium-high pan. Add (mostly drained) tin of tuna in small chunks or large flakes; mix in with half to one (mashed) avocado. Add lots of pepper and a little salt. For more flavour, add pressed garlic and a dollop of store-bought alfredo sauce and/or light mayonnaise. Add well-drained pasta shells and stir well. Serve warm.