This very versatile sauce adds zest to any spring or summer vegetable, hot or cold. You can also serve it over rice or tossed with pasta for a satisfying main dish. The sauce can be conveniently made ahead of time and refrigerated up to three days.
In a medium saucepan, heat butter (or coconut butter). Add leeks and saut?or 10 minutes or until tender. Stir in sorrel and dandelion; cook until wilted. Pour in vegetable stock and maple syrup (or honey) and slowly bring to a boil. Reduce heat and simmer for 10 minutes or until liquid is reduced by half. Cool then stir in yogurt (or kefir) and nutmeg. Season to taste with salt and pepper.
In the meantime, steam asparagus for two to four minutes or until tender yet crisp. Serve with sauce immediately or let cool to room temperature.