I used to just steam or briefly boil collards, but I have a new way now: I cut the stems off, roll the leaves up like cigars, and cut across the cigar in cuts 1/8" apart, making thin slivers of the leaves. Then I heat oil in a wok (or sometimes cook some bacon), saute some garlic and hot pepper flakes in the oil for a few minutes, and then toss in the slivered leaves, which are then tossed in the oil until all coated. About three to four minutes of cooking is enough for young greens; for older ones, I add a little water to the wok and put the lid on, so that the total cooking time is more like ten minutes. A little vinegar rounds off the flavor.
Other greens are doing well too: I scattered kale seeds over one bed in early December, and by late January there was a nice stand of young kale plants. The squirrels dug in the bed, but it didn't disturb them too much.
A flat leaf Italian parsley plant went to seed last summer in the collard bed, and those seeds fell and sprouted to make a sort of understory of parsley plants in the collard bed.
Finally, I planted a few lettuce plants that I bought at a garden center, and they flourished as well.
The "soil" in these beds is a potting mix that was in the beds when we moved into our house. I took out the rose bushes that were in the beds and planted them elsewhere. After I planted the collards, I also collected urine and diluted it 1:10 to water the collards when it was hot and dry last fall. Urine is an under-utilized fertilizer source. It is sterile and harmless to plants if diluted. I read on the internet that the average human produces enough urine in a year to grow over a hundred cabbages!