To rid fiddleheads of any unwelcome dirt or bacteria, you must blanch them in boiling water for a few minutes before sautéing. Ingredients: salt 1/2 pound of fiddlehead ferns 1 tablespoon olive oil 1 garlic clove, thinly sliced 1/2 pound of asparagus, (better if cut into one inch pieces) In a large pot, bring 2 quarts water to a boil, and add 1 tablespoon of salt. Fill a large bowl with water and ice. Add the fiddleheads to the boiling water and blanch for 2 minutes, then drain and transfer to the ice water to stop the cooking. Drain well and blot dry with paper towels. In a large skillet, heat the oil over high heat until it shimmers. Add the garlic and cook, stirring, until it is just colored but not browned, about 30 seconds. Add the fiddleheads, asparagus, and a healthy pinch of salt and cook, tossing frequently.