Step 1

Cook green garlic, almonds, and oil in a small saucepan over medium heat, stirring occasionally, until garlic is golden, about 5 minutes. Let cool until lukewarm, about 5 minutes.

Step 2

Pulse bread in a food processor or blender until finely chopped. Add garlic mixture, bell peppers, cherry tomatoes, cilantro, and lemon juice and process or blend until mostly smooth. Season with salt if needed. Do ahead: Romesco can be made 3 days ahead. Cover and chill.

Step 3

Place a rack in middle of oven; preheat to 425°. Place potatoes in a large pot and pour in cold water to cover; season very generously with salt. Bring to a boil; reduce heat to medium and cover. Simmer until potatoes are fork-tender, about 15 minutes (time will vary depending on the size of your potatoes; be careful not to overcook). Drain; transfer potatoes to a rimmed baking sheet and let cool slightly.

Step 4

Drizzle ⅓ cup oil over potatoes and toss to coat; season lightly with more salt. Using a measuring cup, smash each potato. Roast potatoes until golden brown and crisp, 35–40 minutes.

Step 5

Spread romesco on a platter; spoon potatoes over. Drizzle with oil, top with scallions, and season with sea salt.