In a medium saucepan, heat butter until melted. Add flour and stir until smooth to create a roux.
Change it Up:
Instead of or in addition to basil, try using a combination of other herbs that you like (parsley, sage, oregano)
Instead of pine nuts, use some other nut variety - almonds or walnuts work well.
Substitute store-bought alfredo sauce and/or pesto in place of the homemade sauces.