Cook onions over medium heat for approximately 45-50 minutes, stirring every 5 minutes or so to ensure they cook evenly and don’t stick to the pan. The exact cooking time will vary based on several factors, including the age of the onions and how many you cook at one time.
Once the onions reach the desired depth of color, add white wine to deglaze the bottom of the pan. Add more liquid, if necessary, to scrape up all the brown bits and then season the onions with salt and black pepper, to taste.
Add the sliced mushrooms to the pan with onions and sauté until tender, approximately 5 minutes. Add vegetable stock and pesto to skillet and simmer until heated through, approximately 10 minutes.
Add the Daikon “noodles” and season with salt and black pepper, to taste. Stir to combine and cook for another 4-5 minutes, or until the Daikon “noodles” are crisp tender. Do not overcook.
Remove from heat and serve immediately topped with sliced green onion, if desired. Enjoy!