We eat a lot of deer meat and love to make this gigantic deer meat burger. It's best served with Holly's Horsey Sauce, fresh garden tomatoes and a big appetite (it doesn't hurt to have a big mouth either)!
Place the first six ingredients together in a large bowl and mix well, then form into medium or large sized patties, depending on your preference.
If using deer meat, heat enough extra virgin olive oil in a skillet to cover the bottom of the pan on medium-high (due to the fact that deer meat is so lean, you need the added fat to keep the meat from sticking to the pan). Don't add the extra oil if you are using hamburger meat.
Add the patties to the skillet and cook for about 4-5 minutes on each side, turning only when the bottom is well browned. When the burgers are almost done, turn down the heat to low (drain the fat from the skillet if using hamburger) and top with a slice of Velveeta cheese and allow the cheese to melt. Toast the buns in an oven or toaster oven for a couple of minutes until lightly toasted.
Heat approximately 1 tbs. of extra virgin olive oil and 1 tbs. butter in a skillet on medium high heat. Place the portabello mushrooms in the skillet and heat for 2-3 minutes on each side (just enough to warm the mushroom through). Salt and pepper the mushrooms lightly.
Place a deer burger on a toasted bun, place a portabello mushroom on it and the top deer burger with fresh tomatoes, lettuce, sliced onion and Holly's Horsey Sauce *recipe below*.
Holly's Horsey Sauce: Mix together 1/4 - 1/2 cup mayonnaise (depending on how much sauce you need, it makes a great dip as well) with some fresh ground hot horseradish, as much as you can stand, and mix together well.