Check out this video which walks you through how to make this end of spring seasonal sauce:
1 cup fresh cherries, washed and cut in sixths
1 teaspoon olive oil
¼ cup balsamic vinegar
¼ cup chenin blanc or sauvignon blanc (or any dry white wine)
½ teaspoon crushed garlic
1 teaspoon lemon zest
1 ½ teaspoons yellow mustard seed
½ teaspoon ground fennel seed (roast the fennel for about 3 minutes in a pan, then grind it)
Salt, to taste (about ¼ teaspoon sea salt)
1. Prep all of the ingredients listed above. Preheat an oven to 375 degrees Fahrenheit.
2. Put the slivered cherries, olive oil, and a generous pinch of salt, about ¼ teaspoon, in a roasting dish. Put the cherries in the oven and bake for about 8 minutes. Your task is to just slightly caramelize and cook the cherries—you still want a little firmness and juiciness to each bite.
3. Place the balsamic vinegar, white wine, crushed garlic, lemon zest, yellow mustard seed, and ground fennel seed in a small sauce pot (make sure it is non-reactive—a stainless steel pot works well). Put the pot on medium-high heat. Cook the solution until it is reduced by 90%. Usually the solution can reduce at a medium heat until you are within a minute or two of reaching 90%; when you get close to that point, I recommend turning the heat down significantly because the liquid reduces quite quickly. Remove the pan from the heat as soon as it gets close to a 10% reduction.
4. Once the cherries are oven roasted and the mostarda base is cooked down, place all of the ingredients in the roasting dish (make sure that it is non-reactive) or in the saucepan. Stir the cherry mixture into the mostarda base and check it for salt. You may want to add another pinch of salt to balance the sauce.
5. Set the sauce aside at room temperature for at least two hours to let the flavors mingle and the mustard seed infuse with the cherry liquid. You can make the sauce ahead of time and keep it in the refrigerator for about a week before serving, but fresh sauce is always best.
6. Serve the sauce on top of brined and roasted pork chops, or roasted duck or chicken.