I actually prefer a big, thin patty, like a smashburger, or my favorite fast-food burger, a Whataburger.
Do you have a preference? If so, what is it?
There are a lot of "I's" in my writing that follows, but the question is "my preference"...so...thanks for asking!
I started grinding my own meat some years ago. I prefer my burger cooked medium with some pink in the middle, but concerned about pre-ground meat safety for cooking this way. So, knowing a medium rare steak is perfectly fine to eat (even steak tartar) for those who do not have other health risks concerning their immune system, etc., it was clear to me the safest way to have a medium hamburger was to grind it myself from whole muscle.
I have long abandoned the grilled burger, like you CD I have watched a LOT of cooking shows and finally came to the conclusion that the flat iron griddle (or cast iron non-ridged pan) is the superior way (in my opinion, your mileage may vary) to cook a burger. This from watching the preferences and opinions of many chefs and my own personal experience and preference. Restaurants dont usually use cast iron, they use a pro-griddle which has a thick steel plate as its cooking surface, not something most home cooks have, so cast iron is the next best thing.
I grind my beef from chuck roast. I dont see a need for several meats, but I'm sure that is very good, I just keep that part of my burger life pretty simple. I use the 1/4" die on the grinder and I grind only once, never passing it through again and handle the ground meat very gently. I believe overworking ground beef is one of the main reasons for dense, dry burgers. I form my burgers to their shape only enough so they barely hold together for cooking (no worry about breaking up and falling through grill grates on a griddle pan).
When grinding the meat (I know many already know this but for any who dont) I always cut the beef roast up in to approx. 1" cubes and arrange on sheet pans and put in the freezer until just beginning to get firm on the outside of the pieces. I also chill my grinder parts in the freezer ahead of time. Heat develops in the grinding process and you dont want the fat to start to liquefy. When I feed the cubes in to the neck of the grinder chute, I take care to feed an even balance of lean and fatty pieces for best possible fat/balance/ratio in the ground product. I dont get too scientific about it, but my guess is I usually get 70-75/30-25% lean to fat ratio. I find the best ground beef for burgers when buying it is this ratio as well. Even 80-20 is too lean in my opinion.
Because of my Low Carb eating these days, my burger size has changed. I used to portion 6oz (I am a little obsessed with weighting foods and ingredients, I used to even weigh pasta for perfect portioning when I ate pasta) burgers and form them square to eat on ciabatta bread, but so far, since low carbing, my favorite "bun" for burgers now is
this cheddar biscuit recipe . I make 6 "buns" from this recipe rather than the 10 specified for the portions in the recipe. And now I weigh out and shape 2oz portions for burgers slightly larger than a slider and smaller than the typical burger I used to make. 2 of these burgers makes a very satiating meal because the "buns" bring a solid protein load with them.
To cook smaller and flatter burgers to my liking, which again is medium/pink in the middle, or at least the instant the temp passes this phase is OK and still juicy, rather than intentionally cooking the meat to smithereens like some enjoy; I make sure my cast iron griddle is at least 450° (yes, I'm also temp obsessed and use a laser thermometer to know my pan temps) before putting the burgers on, and cook very fast at the high temp which sears the crust, yet gets the meat off the griddle before its overcooked. This requires a solid "mise en place" to have any toppings ready like cheese, so it can go on the instant the smaller flatter burger is flipped so I am not overcooking the burger waiting on the cheese to melt. Also, room temp cheese is a good idea.
I remove the burgers to a platter with a folded paper towel underneath to catch what are usually significant excess juices (after all, this whole writing is about how to get a properly cooked juicy burger, right?... so mine are ALWAYS juicy) so the burger doesn't carry too much moisture to the "bun".
I stopped making "meatloaf" burgers with a bunch of stuff in them a long time ago. I like to taste a pure burger. It is my opinion that there are no mix-ins needed for burgers, plus doing that just overworks the meat to get stuff evenly distributed. What is required, again, in my opinion, is a strong seasoning of salt and pepper on at least one side of the patty.
I pretty much have this burger thing "down" after about 30 years of previously thinking I knew what I was doing!