How to Make the Ultimate Umami-Bomb Vegetarian Demi-Glace
2 tablespoons sherry vinegar
2 teaspoons Dijon mustard
1/4 cup extra-virgin olive oil
Kosher salt and freshly ground pepper
7 ounces baby arugula (8 cups)
1/2 small red onion, halved and thinly sliced
1/3 cup salted and roasted pistachios
2 ounces ricotta salata cheese
Using a sharp knife, peel the tangerines, removing all of the bitter white pith. Working over a small bowl, cut in between the membranes to release the sections. Squeeze the juice from the membranes into the bowl and discard the membranes. Transfer the tangerine sections to a large bowl, reserving 1/4 cup of the tangerine juice.
In a small bowl, whisk the 1/4 cup of tangerine juice with the sherry vinegar, Dijon mustard and olive oil and season with salt and pepper.
Add the arugula, onion and pistachios to the bowl with the tangerine sections and toss. Using a vegetable peeler, shave the ricotta salata over the top. Season the salad with salt and pepper and toss with 1/3 cup of the dressing. Serve, passing the remaining dressing at the table.