Heat the olive oil in a saucepan over medium heat. Stir in the eschallots and garlic; cook until softened and light brown. Add the bacon pieces and buckwheat; cook and stir until the buckwheat turns orange-ish brown, about 5 minutes.
Add the stock and bring to a boil over medium-high heat. Reduce the heat to low and simmer gently until the liquid is absorbed and the buckwheat is tender, 13 to 15 minutes. Toss with the parsley and season to taste with salt and pepper. Serve immediately.