Slice your onion thin (see post section above for detailed instructions) and add it to a frying pan with your oil or butter on medium heat.
1 large yellow onion, 1 tbsp oil or butter of choice
Rinse, dry, and slice your mushrooms.
8 ounces baby bella or white mushrooms
Continue to sautee the onions over medium heat for about 10 minutes, stirring occasionally with a spatula or wooden spoon, until the onion starts to brown around the edges.
Add the sliced mushrooms and mix well, so that the mushrooms are evenly distributed throughout the onion slices.
Leave the onions and mushrooms over medium heat for 5-8 minutes without stirring to allow for caramelizing process to occur.
Once the onions and mushrooms are golden brown on the bottom, stir a couple of times to turn them, and cook for another 5 minutes or so, allowing them to caramelize on both sides.
Add salt to taste (optional) and serve hot as a side or topping to any savory dish!
¼ teaspoon salt