Quick Mushroom Ceviche

Super simple and delicious with one addition. Mexican hot sauce such as Valentina. Ketchup alone was too sweet for us and it needed a punch of heat. The recipe calls for one small onion but doesn't specify which kind. I take that as use which one you like best or have on hand. I had green onions and a red onion and went with the green onions. Red would be really pretty in this dish but it also might "bleed out" after it sat so I didn't want to take that chance. I served this cold but I think it would have been better at room temperature. I took the picture before I actually served this and totally spaced the avocado but I did serve it with avocado and it is a must. It really helps bring all of the flavors together. I've had a lot of ceviche over the years and this one was definitely unique and one I would make again. Don't forget the hot sauce...