Tuna pasta salad with grapes

1lb pasta (any will do, but I like spirals or tube pasta.)
2 cans tuna (I like a lot of tuna.)
handful of grapes, cut in half
1/2-1c mayo
1t. garlic powder
Optional:
1/2c chopped onion
1/2 c chopped celery
1/2c chopped green pepper

Cook pasta according to package directions. Rinse with cold water and drain well.
Put in bowl.
Add tuna and any veggies you're using.
Add mayo to your desired "creamyness."
Add a dash of garlic powder - approx 1t.
Add halved grapes and incorporate gently.

Serve chilled, toss leftovers after 1 day.