1. Combine plantains, lime juice, and 1/2 cup water in small saucepan. Bring to a boil over medium heat, cover pan, and simmer 20 minutes, or until plantains are very soft. Mash with fork or potato masher, and stir in lime zest. Season with salt and pepper, if desired.

2. Combine beans and salsa in small saucepan; warm over medium heat 3 to 5 minutes, stirring occasionally. Season with salt and pepper, if desired.

3. Spread heaping 1/4 cup plantains on bottom half of each tortilla, leaving 2-inch border. Top with 1/2 cup bean mixture. Fold sides of tortilla over filling, then roll from bottom up. Serve with additional salsa, if using.