0/5
(0 Votes)
Ingredients
- 8 ounces unsalted butter
- 1 medium red onion, peeled and thinly sliced
- 2 cloves garlic, peeled and thinly sliced
- 8 shiitake mushroom stems
- 1 medium ripe tomato, coarsely chopped
- 1 bay leaf
- 1 teaspoon black peppercorns
- 1/3 cup balsamic vinegar
- 1/3 cup water
- Salt and freshly ground black pepper to taste
Preparation
Step 1
Cut 6 tablespoons of the butter into 1/2-inch cubes. Refrigerate.
Melt the remaining butter in a large saucepan over medium heat. Add onion, garlic, mushroom stems, tomato and bay leaf. Cook, stirring occasionally, until the vegetables are soft but not brown, about 6 minutes.
Add vinegar and water. Reduce over medium high heat until just a syrupy liquid remains, about 8 minutes.
Lower the heat slightly. Whisk in the cold butter, 2 to 3 pieces at a time, allowing each addition to be absorbed before adding the next.
Strain through a fine sieve. Season with salt and pepper.
Keep warm over a double boiler.