Preheat the oven to 400 °F (204 °C). Line a half sheet pan with foil. Put the potatoes, oil, and seasonings into a large bowl. If you bowl has a top, even better. Mix all together, making sure the potatoes are thoroughly coated. Pour the potatoes on the foil and make sure they are in a single layer. Drizzle whatever oil is left in the bowl over them. Roast them in the preheated oven for about 15 minutes, then turn them over and roast for another 10-15 minutes or until they are fork tender.
To make these on the outdoor grill, make a foil pouch for the potatoes and roast them using the indirect method.
For the Burgers
Divide the meat into four patties. Put roasted red pepper and cheese on two of the patties. Put the other patty on top and use a fork to seal, then push the seal in so the burgers are a consistent thickness. Sprinkle salt and grate pepper over the patties. Put in the refrigerator until the potatoes are almost done.
Preheat a cast iron skillet on high. When the skillet is very hot, almost smoking, put in the olive oil and swirl it around. Add the patties. Cook on one side for 5 minutes, then flip and cook for another 3 minutes. Test with an instant-read thermometer that the burger is done to your liking. Remove from the skillet and let rest.
Put the beef base and water in the pan and stir vigorously to deglaze and get all the good tasty fond up. Add the Worcestershire and wine. Whisk together. Finally, add the butter and whisk to emulsify the sauce.
If you are doing this on the grill, you would put a pan on the grill and make the sauce in the pan.
Pour the sauce over the burgers, put a piece of cheese, and top with the fried onions.
Notes
I really like the Mezzetta roasted red peppers. However, Sadaf makes good ones, as well as other brands. You can even make them yourself to have on hand.
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