Dandelions are a perennial but Lambs Quarters are a short term annual, so gather the seed and plant them in a row so that they are obviously not a weed. then make succession plantings every 2 weeks so that they can be harvested at their peak. Keep Dandelion roots in the row and put an open top box around them to force tall large leaves for harvest. One friend let his Lambs quarters on the outer edge of the lettuce bed grow tall and go to seed to protect the lettuce from bitterness and early frost.
But those green underneath are certainly not bitter, Lambs quarters are my favorite. But they do not like living where I live.