1. 1. Prepare the Onions: Begin by peeling the yellow onions. Cut them in half through the root end, then slice each half into 1/2-inch thick wedges. Try to keep the root end intact on each wedge to help the layers stay together during cooking. This uniform slicing ensures even cooking.

2. 2. Infuse the Oil: In a large, deep skillet or Dutch oven, heat the olive oil over medium heat. Once shimmering, add the minced garlic and cook for about 1 minute, stirring constantly, until fragrant. Be careful not to let the garlic brown, as it can become bitter.

3. 3. Add the Onions and Seasonings: Carefully add the sliced onion wedges to the skillet with the garlic oil. Toss gently to coat the onions evenly. Sprinkle in the dried oregano, salt, and black pepper. Stir again to distribute the seasonings throughout the onions.

4. 4. Boil and Simmer: Pour 1/2 cup of water into the skillet with the onions. Bring the mixture to a gentle boil, then reduce the heat to low, cover the skillet, and let it simmer for 15-20 minutes. The onions should become very tender and translucent. Check occasionally to ensure there’s still a little liquid and stir if needed.

5. 5. Achieve Crispy Edges: Once the onions are tender, remove the lid from the skillet. Increase the heat to medium-high and continue to cook, stirring occasionally, for another 5-7 minutes. This step allows any remaining liquid to evaporate and encourages the edges of the onions to caramelize and crisp up, adding wonderful texture and depth of flavor. Look for golden-brown edges.

6. 6. Stir in Parmesan: Remove the skillet from the heat. Sprinkle the grated Parmesan cheese over the hot onions and stir gently until the cheese has melted and coated the onions. The residual heat will be enough to melt the cheese beautifully.

7. 7. Garnish and Serve: Transfer the garlic parmesan onion boil to a serving dish. If desired, sprinkle with fresh chopped parsley for a pop of color and freshness. Serve immediately as a warm and comforting side dish.