Turnips can be perturbing little buggers - but once you figure out what to do with them, they are utterly wonderful.
Okay - maybe that's a bit of an exaggeration (the "wonderful" part), but they are a tasty low-carb alternative to potatoes.
To make the pureed turnip dish pictured below - I put two large/diced turnips in a sauce pan with rosemary and two smashed garlic cloves, covered with vegetable stock, and boiled until tender. I then drained, removed the rosemary, pureed in a food processor with a little milk/butter/salt, and drizzled truffle oil on top.
Note: if you want to reduce your turnips' bitter factor - boil in milk or add a potato to the pot (remove before pureeing - the starch will soak up some of the bitterness). Also - add more or less milk to your pureed mixture to take it from a mashed to soup like consistency.