3 pounds dandelion greens (or spinach), trimmed, washed and torn into 1-inch pieces
1/3 cup white wine vinegar
3 tablespoons granulated sugar
Salt and freshly ground pepper
2 tablespoons unsalted butter
In a large heavy pot heat olive oil over moderately high heat. Add greens and toss to coat. Add vinegar and sugar, toss to combine, cover, and simmer for 10 to 15 minutes until tender. Season to taste with salt and pepper. Transfer to serving dish and top with butter.