Step 1

Combine 1/2 cup oil and garlic in a small saucepan over medium-low heat. Cook, swirling pan occasionally, until garlic is tender, 12–15 minutes. Let garlic cool in oil.

Step 2

Meanwhile, preheat oven to 350°. Spread pistachios and pumpkin seeds on a rimmed baking sheet and cook until lightly toasted, 6–8 minutes. Measure out ½ cup nut mixture and roughly chop; season with remaining 1 tsp. oil and 1 tsp. salt.

Step 3

Heat broiler. Broil poblano on a foil-lined baking sheet, turning occasionally, until blackened, 8–10 minutes. Transfer to a bowl, cover with plastic wrap, and let steam 15 minutes. Peel, seed, and roughly chop.

Step 4

Heat a large cast-iron skillet over medium-high heat until a drop of water flicked on the surface sizzles on contact. Add scallions to skillet and press down using the back of a spatula until charred, about 3 minutes. Continue to cook and press until scallions are mostly charred all over, about 4 more minutes. Let cool to room temperature.

Step 5

Combine garlic and oil, poblano, charred scallions, cilantro, lime juice, remaining pistachio-pumpkin seed mixture, and 2 tsp. salt in a blender and process until smooth, scraping down sides of machine as needed (you may need to add a tablespoon or two of water to keep things moving).

Step 6

Transfer dip to a plate and top with chopped pistachio-pumpkin seed mixture, cilantro leaves, and radishes, if using. Squeeze lime juice over and scatter with scallions. Serve with sturdy crackers.