Here's my general GF plain foods list:
Potatoes (mashed, boiled, baked, fried, potato chipped; white, red, gold, and sweet varieties)
Corn (cob, frozen, canned, mission tortilla, popcorn cooked on stovetop)
Squash: (spaghetti squash with tomato sauce and cheese OR butter and herbs, acorn/butternut squash with butter, spices, cane sugar, pumpkin pudding)
Rice (white, brown, boiled, baked, rice pudding, hot rice cereal)
Buckwheat (cakes, Bob's Red Mill has GF...