Bring a large pot of unsalted water to the boil
Meanwhile, remove stems from the greens and wash greens well. Cut greens into largish pieces and keep each type separate to accommodate different cooking times
Add the kale to the pot, cover, and cook 2 minutes.
Add the chard, cover and cook 2 minutes.
Add the mustard greens and spinach, cover and cook 4 minutes.
Drain well and transfer greens to large bowl of cold water. When cool, drain, and squeeze as much water as you can from the greens. You should have 12 to 13 ounces of blanched greens.
Chop them finely with a large chef’s knife.
To cook, heat ¼ cup olive oil in a large skillet over medium heat. Add the red pepper flakes, if using, and the leek and scallions. Cook, stirring occasionally, until vegetables are translucent, about 5 minutes.
Add the chopped greens, and cook, stirring, for 5 minutes. If vegetables seem dry and want to stick to the pan, add small amounts of water as needed.
Take the pan off the heat and cool completely.
Add the cheeses, dill, and parsley. Taste carefully for salt and add if needed.
Stir in the eggs and cream.