Dandelions, chicory, thistles and wild lettuces are some of the most nutritional edible wild plants you can harvest but in their rawest forms they are very bitter and generally uneatable by any but the most die-hard foragers. Luckily, it is very simple to turn these plants into dishes that are not just eatable but actually delicious. It always helps to pick the leaves at the proper time (early young leaves before the flower stalk(s) have appeared) but these tricks will even help with late-harvested, extremely bitter leaves. These four different methods are as follows:
2. wilting with hot grease or oil
3. diluting with mild greens
4. overpowering the bitterness with salt, sour, and/or tart flavors
Many of the bitter-tasting chemicals in these plants are soluble in hot water and so can be removed with 1-3 changes of boiling water. However this method also removes/destroys some of the nutrients so you'll need to increase the amount of greens you are cooking.
Cover the greens in excess water, boil for 10 minutes, then rinse of and taste a small bit of the plant. If it's still too bitter pour off this water and replace it with fresh water, then boil for another ten minutes. Keep doing this until the greens are edible. The resulting mass will be unattractive and lacking in the more water-soluble "good" chemicals, but the protein and other large phytochemicals will remain.
Wilting with hot grease or oil
This is my particular favorite method. Drizzling hot bacon grease or hot seasoned olive oil causes a chemical change to the bitter molecules and also leaves a protective coating on the tongue which reduces it's sensitivity to bitter flavors. Bacon/egg/sow thistle omelets are a Sunday morning treat at our house. The hot bacon grease converts the bitterness to a rich, deep flavor that I can't really describe other than to say I (and my young daughters!) find it to be fantastic. Vegans can use olive oil though for some reason I find the results to be inferior to bacon grease.
Don't completely cover the greens in the hot oil/grease, just dribble it on so most of the leaves have become a little "crinkly". I like to include a variety of bitter plants in the bowl to give a very complex mix of flavors. You will have to experiment a little to find the amount of wilting you prefer but luckily most of these plants are plentiful and it's easy to harvest plenty.
Diluting with mild greens
This is the best way for raw-foodists to incorporate dandelions and the such into their meals. It retains all the beneficial chemicals though it does require having assorted mild greens such as dayflower, young dollarweed, plantain, chickweed, amaranth, young hibiscus and turk's cap leaves, or even regular lettuce.
Finely chop or shred the bitter greens and combine them with the mild greens in a ratio of 1 part bitter-9 parts mild. This will greatly cut the bitterness to just the point of adding a unique flavor to your salad. As you grow accustom to the flavor you can increase the bitter portion, but few will go more than 3 parts bitter-7 parts mild.
Overpowering the bitterness with salt, sour, and/or tart flavors
The tongue, while amazingly sensitive to flavors, can be overwhelmed at times. Combining the bitter greens with soy sauce or a tangy red wine/vinegar dressing over-stimulates most people's taste-buds resulting in a reduced ability to taste the bitterness. This technique is another favorite of vegans and raw-foodists.
A similar effect occurs when incorporating the greens into homemade sauerkraut or kimchi. The sour fermentation of these foods will help break the bitterness though it requires more experimentation due to the unequal levels of bitter chemicals from plant to plant. In my opinion that is part of the fun of wild foods, though!
Buy my book! Idiots Guide Foraging covers 70 of North America's tastiest and easy to find wild edibles shown with the same big pictures as here on the Foraging Texas website.