Layer your cutting board with a clean cotton towel and three layers of paper towels. Place tofu slices on top of the towels. Place a layer of three more paper towels on top of tofu, and cover with another cotton towel. Carefully place another cutting board or cookie sheet on top of the towels. Stack something heavy on top of the board, like a cast iron skillet, a large can of beans, heavy bowl or other weight to press down on tofu. Let sit for at least fifteen minutes, and up to one hour.
While the tofu is pressed, roast the poblanos and the red peppers, until well charred and blackened. Allow to cool, peel, and remove seeds and membranes. Roughly chop all four peppers, setting one chopped red pepper aside and place the remaining 3 peppers in the bowl of a blender.
Add the chopped onion, tomato paste, water, spices, salt, and chipotle paste to the bowl of the blender. Process until smooth. Pour the sauce into a crock pot.
Heat 1 tablespoon oil in a large skillet. Working in batches, fry the tofu slices until golden brown. Cut tofu into cubes, and press of some of the cubes to shred the tofu.
Add cooked tofu and the reserved chopped red pepper to the crock pot and stir to coat the tofu in the sauce.
Cook tofu on low for 2-4 hours. Serve Copycat Chipotle Sofritos in tacos, burritos, bowls, tostadas, any way you like!