Bring a large pot of water to the boil for the tortellini.Heat the butter in a medium-large saucepan.
Add the garlic and cook over low heat for 1 minute.
Stir in the flour and cook, stirring over medium-high heat, for 2 minutes.
Gradually whisk in the milk and the wine and bring to the boil, stirring almost constantly.
Reduce the heat to moderate and cook the sauce for about 2 minutes until it is smooth and thick.
Stir in the spinach and heat through.
Reduce the heat to low, add the cheese and cook, stirring, until the cheese is melted.
Season with the salt, Tabasco and nutmeg.
Add salt to the pasta water and cook the tortellini at a rapid boil for about 5 minutes or according to package directions until al dente.
Drain well in a ander.Reheat the sauce over low heat.
Spoon the sauce over the hot tortellini and grind black pepper over the top before serving.