Try making this savory snack for your next Halloween party. The skins of waxy potatoes wrinkle when roasted and a pool of peppery romesco sauce makes a delicious pairing. Stick a single toothpick in each potato for easy dipping.
Preheat oven to 350 degrees. Toast almonds in a single layer on a rimmed baking sheet until lightly golden and fragrant, 7 to 8 minutes. Transfer to a plate to cool.
Meanwhile, roast red peppers directly over a gas burner flame until blistered and charred, turning with tongs as each section blackens. (Alternatively, broil peppers on a baking sheet.) Transfer peppers to a large bowl and cover tightly with plastic wrap; let steam about 15 minutes. Using paper towels, peel off blackened skins; remove and discard stems and seeds.
Lower oven to 325 degrees. In a food processor, pulse almonds, roasted red peppers, pimenton, mint, vinegar, garlic, and 3/4 teaspoon salt to a coarse paste, about 1 minute. With machine running, add 1 tablespoon oil in a slow, steady stream through the feed tube until smooth. Transfer to a bowl.
Place potatoes on a rimmed baking sheet and toss with remaining 1 1/2 teaspoons oil and 1/4 teaspoon salt. Roast in oven (without moving potatoes on the pan) until skins are slightly crisp and potatoes are tender, about 1 1/2 hours. Serve potatoes warm or at room temperature, with sauce on the side.
Romesco sauce tastes even better the next day, when the flavors have had a chance to blend. Refrigerate it overnight in a covered container, and bring to room temperature before serving.