Bring to a simmer, cover and cook for 10 minutes.

Bring to a simmer, cover and cook over low heat for 15 minutes.

Bring to the boil, then lower heat, cover and simmer for one hour.

Bring to a simmer, cover and cook 15 minutes, until tender.

Bring to a gentle simmer, cover and place in the oven for about 20 minutes.

Bring to a boil, cover and cook over high heat for about 8 minutes.

Bring to a simmer, cover and place in the oven for two hours.

Bring to a boil, cover and simmer for 45 minutes.

Bring to a boil, cover and cook over moderate heat for 15 minutes.

Bring the mixture to a boil over high heat, and cover.