Spinach Artichoke Dip (Restaurant-Style)

Bahan-bahan (4 porsi)

• 4 tablespoons unsalted butter
• 1 cup finely chopped yellow onion ((from 1 medium onion))
• 2 cloves garlic, (minced)
• 2 tablespoons all-purpose flour
• 1¾ cups half & half, (plus a few more tablespoons if needed)
• 1 (10-ounce) box frozen chopped spinach, (thawed, drained, and squeezed dry)
• 1 (14-ounce) can quartered artichoke hearts, (drained, rinsed, chopped, and blotted dry with paper towels (see note))
• 2 oz (¼ cup) cream cheese
• 2 cups shredded extra sharp Cheddar
• ½ cup grated Pecorino Romano (or Parmigiano Reggiano)
• ¾ teaspoon salt
• ¼ teaspoon freshly ground black pepper
• Pinch nutmeg
• 2 teaspoons Frank's RedHot sauce
• Tortilla chips, (for serving)