Warm the caramelized onions in a pan over low heat.
In another pan, wilt the spinach in the water clinging to its leaves, then season it with salt and pepper. Slice the peppers into wide strips.
Toast the bread, then rub one side with the garlic. Cover with the onions, followed by the spinach, the cheese, then the roasted peppers set diagonally across the top.
Season with salt and pepper, and drizzle with olive oil.
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