Brown Butter Sauce

 4 tablespoons butter
1 ounce fresh sage, leaves picked off stems
1 bunch mustard greens
1 cup chicken stock
Melt the butter in a pan over low heat. When melted, add sage. Heat until the butter just begins to brown and sage is fried. Deglaze pan with chicken stock and then fold in mustard greens. This sauce is especially taste served over squash ravioli.