1-Getting Started with Your Ingredients: First, peel and thinly slice 4 medium yellow onions to ensure even cooking, as mentioned in the essential ingredients. Heat 2 tablespoons of olive oil in a 12-inch cast iron skillet over medium heat, making sure the pan is ready for the onions. Add the sliced onions and sauté for 5 minutes until they begin to soften, setting the stage for that deep golden color.

2-The Cooking Process: Sprinkle with 1/2 teaspoon salt, then reduce the heat to medium-low, and cook for 50 to 80 minutes, stirring every few minutes until the onions are very soft and caramelized. If the onions start to stick, reduce the heat to low or add a splash of water to keep things moving smoothly. For faster results after 50 minutes, increase the heat to medium and stir constantly to intensify the caramelization without burning.

3-Final Touches and Adaptations: Once done, remove from heat and let the onions cool slightly before using them in your favorite meals. This step-by-step guide works for vegan, gluten-free, and low-calorie diets by sticking to basic oils and seasonings. Keep in mind tips like using a large skillet to allow moisture evaporation and slicing onions evenly for consistent cooking.