Traditionally tagliatelle is the pasta that is paired with bolognese but I often will serve it with fettuccine, as in these photos, or a pappardelle. If I am out of long and flat pasta I will grab a box of rigatoni or penne to serve with the bolognese sauce. The choice is up to you but these are my suggestions. I would advise a hearty past instead of a delicate pasta such as an angel hair pasta.