Pepperonata

A traditional Italian sweet pepper stew that Joe Bastianich (MasterChef ™ Season 15) described as "fantastic. That's a hard thing to make."  

This dish typically consists of bell peppers slowly cooked with onions, garlic, and sometimes tomatoes until jammy and concentrated. The technical difficulty lies in achieving the perfect balance of sweetness and acidity while cooking the peppers down to the proper silky texture without burning.