How to Make It
Preheat the oven to 400°. In a medium bowl, toss the shredded parsnips with the tarragon, salt, pepper and rice flour. Add the egg and mix well. Form the parsnip mixture into 12 cakes.
In a large ovenproof nonstick skillet, melt the butter in the olive oil. Fry the parsnip cakes over moderate heat until nicely browned, about 1 1/2 minutes per side. Transfer the skillet to the bottom third of the oven and bake the parsnip cakes for about 15 minutes, or until cooked through. Serve warm, with sour cream.