Greens and Beans with Mushrooms

This recipe mimics a great Italian dish called "Greens and Beans" which gets very heavy. Too heavy for me! Here I have lightened the load by using swiss chard greens, with spinach, mushrooms, and leeks- and last but not least- beans!
Ingredients:
2 large bunches of rinsed swiss chard, de-veined and loosely chopped
3-4 cups of baby spinach, washed
2-3 leeks, rinsed well and chopped (see here to learn how to chop leeks)
1 container baby bella mushrooms, chopped
1 can of white northern beans, drained and rinsed
1 lemon juiced
2 tablespoons olive oil
3 cloves garlic, minced
salt and pepper
1/3 cup grated parmesean cheese
Begin by rinsing the mushrooms you have and giving them a rough chop, set aside. Next rinse the chard and remove the veins. I wash the leaves as I remove them from the stalks and pat dry on a towel. Repeat with spinach, but there is no need to remove stems, unless you really want to! While the greens are drying, remove all the dark portion of the leeks, and slice them down the center, lengthwise. Rinse each half really well with water and slice into half-rings. Place all things green aside, while you begin to mince garlic and heat oil in the LARGEST skillet you have. Make sure you also have a lid for said skillet. Once oil is heated, on medium to high, add the leeks and sautee about 3-4 minutes before adding the garlic and chopped mushrooms. Continue to sautee until they begin to soften, another 3-4 minutes. Now you want to add the beans, 1/2 of the juiced lemon, salt and pepper to taste. Sometimes, I add a few pinches of red pepper flakes OR even some cumin, depending on how spicy you like things. Options are limitless with seasoning, but often I prefer the tang of lemon and parmesean cheese. Finally, add all of the green leaves to the pan. Just go ahead and pile them on there and turn down the heat to low and cover. You will need to leave the pan alone for at least 4-5 minutes before you remove and give it a good toss. If the leaves don't look completely wilted, re-cover and continue to cook. BUT if they are all wilted down, add the last of the lemon and toss to coat while in the pan. The beans, yeah, they might stick a little, and that's OK. Serve with rice, bread, or any type of meat, and top with shredded parm.