I've put together a couple of options for the turnip soup. One is a cream version, one is a thinner stock version. The stock version would be more period-appropriate, and could be thickened with some mashed beans or peas. Oats or other grains could also be used to thicken the soup, as could pieces of bread. These options make more of what is called a pottage.
An important note on broth and stock: There's a difference between stock and broth. Stock is made with bones, and broth is not. For veggies, it's kind of the same thing, both being made with fresh veggies. You can save all sorts of extras in a freezer bag, then make veggie stock when you have a full gallon-sized bag. Peels, skins, bruised pieces, etc. all work very well for stock. For meat stock, use raw bones along with the vegetables. Be sure to either tie it all up in a cheesecloth, or strain the stock well to keep out little pieces of unwanted bits. Freeze the stock in ice cube trays, then toss the cubes into freezer bags and label. You will have fresh stock on hand all the time! You can make stock in the crock pot, too! Put it all in the pot, cover with water, turn on low for 12 hours.
Cream of Turnip Soup
1 c. peeled and diced turnips
1/2 c. scraped and diced parsnips
1 1/2 c. beef or lamb stock (this really needs a meat stock for the flavor)
1/2 c. coarsely ground almonds (don't use the salted or roasted ones. Raw almonds here!)
1 c. heavy whipping cream
3 egg yolks
1/2 t. salt
Juice of 1/2 lemon
Gently simmer the turnips and parsnips in the broth until soft, 10-12 minutes or so. Stir in the almonds and heat for 2-3 minutes. In a separate bowl, break and mix the yolks and salt with the cream. Next, add the lemon juice and slowly pour 1/2 c. of hot soup into egg mixture, stirring well as you pour in the soup. This will temper the egg mixture so you don't get scrambled egg soup! Slowly pour this tempered mixture into the soup pot and stir it well. Continue heating for about 5 minutes on low heat, stirring a couple of times. Serve piping hot with fresh bread!
4 c. stock (beef, chicken, lamb or vegetable)
1 c. peeled and diced turnips
1 c. chopped leeks
1/2 c. peeled and diced parsnips
1-2 chopped white carrots (wild carrots are white or purple, but orange ones will do fine!)
2-3 ribs of celery, chopped
1 onion, peeled and diced
3 cloves of garlic, peeled and diced
1/2-1 lb. cooked or 1 can chichees, drained and rinsed (optional)
Put all of the above in a crock pot or stove-top pot and stir. Simmer for 30 minutes or so. If you use a crock pot, I'd recommend setting it on low for 4-6 hours.
chopped roasted pork or lamb (This is optional, but a great way to use leftover meats)
juice of one lemon, plus the lemon zest of half the lemon- can add zest of the whole lemon if desired
fresh herbs- chopped
fresh chopped chard or spinach leaves
Put these in and stir gently. Simmer another 20-30 minutes, until all vegetables are softened and the greens have wilted.