Mix up some salt and pepper to your liking, and rub all over the skirt steak, then place in a gallon sized plastic bag then refrigerate for at least an hour. You can do this up to a day ahead to help tenderize the meat.
Into the saucepan goes the wine and balsamic vinegar. On the stove top, bring the wine and balsamic vinegar to a boil, then reduce heat and reduce sauce until it becomes thicker, and so it clings to the spoon like a thin gravy, whisking occasionally. Once it reduces, take it off the stove, whisk in a pinch of cayenne pepper and honey. Pour into a cup or gravy boat, then set aside.
On the stove top, heat a couple of pats of butter in an iron pan/skillet, drizzle some olive oil in the pan (helps avoid the butter from burning).
On medium-high to high heat, sear the skirt steak so each side is nice and brown. While the meat is cooking on one side, occasionally give the top side a quick baste with the butter/oil that's in the pan with a large spoon... carefully, giving it a quick splash/baste. (Since this meat will finish cooking by broiling in the oven, it's really important that the heat in the pan is high so you can get a nice brown sear on each side, without actually cooking the meat throughout, especially since skirt steak is not a very thick cut of meat. I recommend wearing some kind of protection on your hands like an oven mitt to avoid any scalding injuries.)
Turn off the stove, remove the skirt steak from the burner, place a couple of pats of butter on the skirt steak and rub a little, but not so the pats of butter completely melt .
Place the iron pan/skillet with the skirt steak on the top rack of the oven broiler, which you've preheated to 450F and broil for 12 minutes. If the skirt steak is less than 1/2 inch thick, then just broil for 8 minutes. While the steak broils...
Toast some pine nuts in a dry skillet or grill pan...toast to your liking. Take off the stove and set aside.
Take the skirt steak out of the oven, place on a clean cutting board, and let the cooked meat rest about 10 minutes.
While the meat is resting, start assembling your plate by placing some fresh spinach on a plate.
After the meat has rested, slice it about 1/4 of an inch thick and fan out a few slices over the bed of spinach, drizzle the red wine balsamic reduction over the meat and a little but on the spinach and around the plate ever so lightly. Sprinkle with toasted pine nuts and, well... eat it!