Littleneck Clams with New Potatoes and Spring Onions

Name: Littleneck Clams with New Potatoes and Spring Onions
Ingredients: 3 tablespoons olive oil; 4 ounces smoked Spanish chorizo, cut into 1/4 pieces; 1 1/2 pounds small new potatoes, sliced 1/4 thick; 1 bunch spring onions or scallions, whites halved and sliced; greens sliced on a diagonal, divided; 4 garlic cloves, thinly sliced; 1 cup dry white wine (such as Sauvignon Blanc or Pinot Gris); 5 pounds littleneck clams, scrubbed; Toasted bread (for serving); Ingredient info: Spanish chorizo is available at Spanish markets, specialty foods stores, and online.