Slowly saute or sweat onions and garlic in oil in a partially covered saucepan until very soft but not browned. Add lentils and 4 cups stock and cover and cook slowly for 25 to 30 minutes or until lentils are very soft. Cool slightly and puree in a food processor or blender until very smooth adding additional stock for desired consistency. Season to taste with salt, pepper and lemonzest. Use as a base for cream soups and sauces. Store covered in refrigerator up to 1 week or in freezer up to 6 months.
This recipe yields approximately 2 1/4 cups.
Comments: To cook white lentils so that they hold their shape for salads, pilafs, etc. Rinse the lentils repeatedly in cold water in a strainer until the water runs clear. Add 1 cup rinsed lentils to 2 cups stock or water and bring to a boil. Reduce heat, cover and simmer for 8 minutes. Remove from heat and allow lentils to sit for another 10 to 15 minutes. Drain if desired. Since white lentils have a potato-like flavor, I also like to take them at this point and heat them up and mash them a bit with a little butter, freshly-grated Parmesan and some chopped fresh herbs. A great risotto alternative.