Before eating a meal, say:

Christ, Bread of Life,
Come and bless this food. Amen

Or

Bless us, O Lord, and these your gifts, which we are about to receive from your bounty;
through Christ our Lord. Amen

After a meal, say, as you make the Sign of the Cross:

+ May the Lord, who has fed us on earth,
bring us to share His banquet in heaven. Amen