Have you tried offering him plain cooked (canned is fine if you rinse the salt off) beans? They are finger food for little kids that are old enough to not inhale and choke.
Tofu is cooked as part of the manufacturing process, so no further cooking is necessary. My 15-mo-old granddaughter loves tofu cubes just plain, no seasoning added. I just offer her some cubes on her plate along with an assortment of veggies, and she gobbles it all up. If you want to season tofu, you can add most any seasoning you want, as it has almost no flavor of its own.
I use soft tofu to "stretch" scrambled eggs, and have served it to people who never suspected they weren't eating scrambled eggs. I'm certain you could make a tasty "scrambled egg" dish with only soft tofu. Here's what I'd use: One box soft tofu
Chicken broth seasoning - I use McKay's Chicken Seasoning which is vegetarian and has no MSG.
Turmeric as needed
Frying pan with oil of choice for frying
Mash the tofu in a bowl until it is the consistency of cooked stirred scrambled eggs, kind of chunky. Season to taste with chicken broth seasoning being careful not to make it too salty. Sprinkle lightly with turmeric if you want to make a little more yellow.
Heat frying pan gently; add "eggs", stir until water evaporates and "eggs" are heated through. Serve plain, with toast, with cheese, catsup, salsa, or whatever you'd put on regular scrambled eggs.
There is a plethera of recipes for tofu on the internet. You could start by searching vegetarian and vegan recipe sites, and tofu sites. It is really a very versitile food.