1/2 lb acini di pepe or orzo (1 1/4 cups)
2 tablespoons olive oil
2 tablespoons unsalted butter
3 garlic cloves, minced (1 tablespoon)
1/4 teaspoon dried hot red pepper flakes
3 scallions, chopped
1 (10-oz) package chopped frozen spinach, thawed and squeezed dry
1/2 cup crumbled feta (3 oz; preferably French)
Accompaniment: lemon wedges
Cook pasta in a 4- to 6-quart pot of boiling salted water, uncovered, stirring occasionally, until al dente, then drain well in a coarse-mesh sieve. Transfer to a bowl and keep warm, covered.
Meanwhile, heat oil and butter in a 12-inch heavy skillet over moderately high heat until hot but not smoking, then saut� garlic, red pepper flakes, and scallions, stirring occasionally, until garlic is golden, about 2 minutes. Add spinach and cook, stirring, until heated through, about 4 minutes.
Toss pasta with spinach mixture and feta until combined. Season with salt and pepper.
Makes 6 side-dish servings.