If you're like me, you can't afford to use chopped filet of beef very often. If you can so much the better but obviously the better quality cut of meat the better quality the burger.
For a "normal" patty, use about 5 1/2 oz of very cold cubed filet of beef or your favorite cut. The reason for the cold temperature is because it's just easier to chop than if it's completely thawed or at room temp. I "chop" my meat for burgers in a food processor as opposed to "grind" in a meat grinder. I think the texture is better and it helps to keep the meat tender no matter what doneness it's prepared. Weigh out and chop 5 1/2 oz at a time and prepare each patty for the same reason. Just for looks and consistency, I use a 4 inch ring mold to form the patties. Once the meat is chopped and the patty is formed, allow it to come to room temperature before beginning to sear.
In a HOT cast iron skillet, add about 2 tbs Extra Virgin Olive Oil and allow it to get to just below the smoke point. Add your room temperature patties, no more than two at a time, and get a good sear. Most people want to keep flipping the burger. Make yourself leave it alone and let it brown on that side. When you are able to lift the patty with NO resistance, (3-5 minutes) flip and sear the other side. This is when you can add your onion slices and pickled jalapenos. Medium rare won't take long so keep a close watch. Use an instant read thermometer if you have to. Once done to medium rare, spoon 1-2 tbs pimento & cheese on the burger and allow to melt. (Yes, if you don't have p&c, use your favorite sliced cheese.) Remove to a plate and allow to rest. (Cover with tin foil to keep the heat in.) Finish sauteing the onions and peppers.
Prepare a toasted bun. Adding mayonnaise to at least the bottom half of the bun will help keep any meat juices from soaking in and through the bun. Add you patty, top with the onions & peppers, eat...ENJOY!