Source: Farmer John’s Cookbook: The Real Dirt on Vegetables by John Peterson and Angelic Organics
Toast the walnuts in a dry, heavy skillet over high heat until start to brown and become fragrant. Be careful not to over toast them!
Heat butter, 1 tablespoon of the oil in a large skillet over medium low heat. Add the leeks and let cook until soft and golden brown – about 45 minutes. Remove from heat and let cool.
Place salad greens in a large bowl. Add salt, pepper, balsamic vinegar and olive oil and toss. Arrange greens on four plates. Add leeks, pear slices and sprinkle on walnuts and cheese.