diz14 I always put lentils in any mince based meal these days and add extra vegetables to all casseroles and stews so that average meat portion is smaller.
Less easy with a roast, but Yorkshire puddings can go back to their original purpose, which was to fill you up before the meat, so that you didn't want to eat too much meat.
In Charlotte Bronte's 'Shirley' one character says to his children 'No ball without broth, no meat without ball' In other words you do not get the meat until you have eaten your soup and your 'ball'. which would be a Yorkshire pudding, dumpling or other dense carbohydrate, so you were pretty full before you started on the meat.
I am very economical with meat, portionwise because I only by environmentally supportive Pasture for Life meat, which is expensive , but because the portions served are small, is more economical.