Step 1: Pickle the Onion
Get started by preparing the flavors that will elevate your flatbreads. Line a baking sheet with foil and place it on the top rack of your oven. Preheat the oven to 450°F and wash all your produce thoroughly. Halve the onion, peel it, and slice it thinly. Drain the pineapple over a small bowl, reserving its juice for later. To make the pickled onion, combine ¼ of the sliced onion, half the vinegar, and a pinch of salt in the bowl with the pineapple juice. Stir well and set it aside to soak up all those tangy flavors.
Step 2: Cook the Onion
Bring a frying pan to life with a drizzle of oil over medium heat. Add the remaining sliced onion and cook, stirring occasionally. Splash in a bit of water if the pan starts to dry out, to prevent sticking. Cook for about 6 to 8 minutes, until the onion softens and becomes translucent. This is where their sweetness starts to shine.
Step 3: Prepare Additional Ingredients
While the onion cooks, grab your green pepper and get chopping. Halve the pepper, remove the core, and slice it thinly into strips. Toss the strips into a small bowl with a drizzle of olive oil, a pinch of salt, and freshly cracked pepper. Next, dice the fresh mozzarella into small ½-inch cubes. With everything prepped and ready, you’re setting yourself up for smooth assembly.
Step 4: Caramelize the Onion and Pineapple
Now it’s time to bring depth and sweetness to the dish. Turn up the heat to medium-high and add the pineapple to the softened onion. Stir everything together and cook until the pineapple takes on a lightly caramelized golden hue, about 2 to 3 minutes. Pour in the remaining vinegar and continue cooking for another 1 to 2 minutes, stirring constantly, until both the onion and pineapple are jammy and irresistible. Turn off the heat and season with salt and pepper to taste.
Step 5: Assemble the Flatbreads
Grab your flatbreads and brush each one with a drizzle of oil for that perfect golden crust. Carefully pull the baking sheet from the oven and place the flatbreads on top. For maximum flavor, evenly spread the BBQ sauce over each bread. Then layer on the caramelized onion and pineapple mixture, the green pepper strips, Monterey Jack cheese, and the diced mozzarella. Every bite should be loaded with cheesy, tangy goodness!
Step 6: Bake and Serve
Slide your loaded flatbreads back into the top rack of the hot oven. Bake for 10 to 12 minutes, keeping a close eye as the cheese melts into gooey perfection and the edges of the bread crisp up to golden brown. (For 4 servings, rotate the baking sheets between the top and middle racks halfway through.) Once baked, transfer the flatbreads to a cutting board and finish them off with the pickled onion (draining it first, to taste). Slice into quarters, plate them up, and get ready to dazzle your taste buds!
