I like to cook up some bacon and red onion and throw in some maple syrup and red wine vinegar then wilt in the chard and you have a lovely warm salad. You could add some walnuts after it's done too or other raw nuts of your choice.
Pure de acelga, my MIL taught me this. I think it's Argentinian. I don't have exact measurements, but you get the idea in the directions. Bring large pot of water to boil with some salt. Add fuck ton of chard, two large armfuls, stems and all. Cook until softened but not overcooked. I drain it when it turns bright green, a few minutes at most. Make a simple white sauce or Bechamel. You want to end up 2 cups of white sauce: equal amounts butter and flour (start with 1/4 or cup each) melt butter, add flour and cook until flour loses raw taste, add milk (maybe 1 or 2 cups) and whisk on med heat until you have a creamy sauce. Add some grated nutmeg, not too much. Puree the cooked chard in blender, try not to add too much water. Mix chard with white sauce to make a lovely green sauce. You can adjust white sauce to chard ratio,as you lile, I go heavy on the chard. Adjust salt, pepper, and nutmeg. Serve on day old toasted slices of country bread (or homemade whole wheat bread, don't use soft white bread, needs to not turn to mush). Garnish with hard boiled egg slices on top. Cheap, delicious, uses up old bread. You can also put the sauce on fish.