Beet Salad with Feta and Pumpkin Seeds

Preheat the oven to 400°F (200°C).
Cut any greens off the beets and discard or reserve for another use, leaving about 1/2 inch (1 cm) of stem. Scrub the beets under running water and pat dry with paper towels. Place the beets in a large roasting pan and toss with 2 tablespoons olive oil and salt.
Pour the water into the roasting pan and cover tightly with foil. Roast beets until tender when pierced with a knife, 50 to 60 minutes. Note that roasting time will depend on the size and type of beets.
Remove foil from the roasting pan and set aside until the beets are cool enough to handle. Peel the beets and then slice into wedges.
In a medium bowl, whisk the remaining 1/2 cup olive oil, sherry vinegar, and shallot. If using more than a single color of beet, divide the dressing into multiple bowls to prevent darker beets from bleeding their colored juices into the lighter beets. Add the beet wedges to the bowl(s) and toss with the dressing. Marinate the beets for at least 2 hours at room temperature, or refrigerate, covered, for up to 12 hours.

While the beets are marinating, set a large cast-iron skillet over medium heat. Add the pumpkin seeds and toast, stirring constantly, until puffed and slightly brown, about 10 minutes. Drizzle with olive oil, sprinkle with kosher salt, and stir to coat. Remove skillet from the heat. Reserve 1/4 cup pumpkin seeds for the salad. (The remaining pumpkin seeds may be cooled and stored in an airtight container for up to 3 days.)

In a blender, combine the onion, oil, vinegar, sugar, mustard, and salt and pepper, to taste, and whiz until creamy, about 1 minute.

Drain the beets and discard the marinade. In a medium bowl, gently toss the marinated beets with the watercress and House Vinaigrette. Garnish with 1/4 cup salted pumpkin seeds and the crumbled feta. Season with salt and pepper and serve.