Instructions
- Prepare the filling: Heat the olive oil or butter in a large skillet over medium heat. Add the finely diced onion and cook for 2–3 minutes, stirring often, until softened and translucent. Stir in the minced garlic and cook for another 30 seconds until fragrant, being careful not to let it brown.
- Add the chopped shrimp to the skillet and cook for about 2–3 minutes, or until they turn pink and opaque. Stir in the crab meat, season with salt and pepper, and cook for another minute to blend the flavors. If using spinach, stir it in at this stage and cook just until wilted.
- Remove the pan from heat and allow the mixture to cool slightly. Transfer to a large mixing bowl and stir in the ricotta or cream cheese along with half of the grated Parmesan. Mix until the filling is creamy and evenly combined. Set aside.
- Make the sauce: In a medium saucepan, melt the butter over medium heat. Sprinkle in the flour and whisk continuously for about 1 minute to create a smooth roux. This step eliminates any raw flour taste and ensures a velvety sauce.
- Gradually pour in the milk or cream, whisking constantly to prevent lumps from forming. Continue cooking and whisking until the sauce thickens enough to coat the back of a spoon, about 5 minutes. Stir in the lemon zest and juice, then season with salt and pepper. Remove from heat and set aside.
Assemble the cannelloni:
