Step 1

In a slow cooker, combine tomato sauce, sugar, molasses, chili powder, 3/4 cup water, and 1/2 teaspoon salt. Finely chop garlic and 1 3/4 onions and stir into sauce along with jackfruit. Cover and cook on High until very tender, 3 to 4 hours.

Step 2

Ten minutes before serving, whisk together lime juice, agave nectar, and 1/4 teaspoon each salt and pepper. Thinly slice remaining onion quarter and toss with lime juice mixture.

Step 3

Using two forks, gently break up jackfruit. Toss onion with pineapple and fold in cilantro. Divide jackfruit among rolls and top with avocado and pineapple slaw.