If you take little portions SOMEONE is always going to say "you need to eat more - I didn't bring the mega cheesecake so you could pick at it" unintentionally sabotaging your efforts.
Though I still laugh at the time, while dieting and eating at my Dad's house with family, my Dad said "you're picking at your food, you eat like a bird!" to which my big brother grinned and said "yea, RODAN!" which cracked us both up. I really miss him.
What is working for me is to have just small servings of the higher fat, higher calorie "good" stuff, , make your treats or baked items smaller sized so the little ones can enjoy one without you eating a piece the size of a brick and filling up your plate with fruits and veggies so you, and those around you have a sense of a hearty meal.
For breakfast - eggs, sausage and mini scones (served on salad plate). I made some bacon for my husband but I was satisfied with the nibble of sausage (provided I stayed upwind of the bacon cooking)
The scones -
In bigger bowl
2 cups self raising flour (in the UK, I believe it's "self-raising")
mix and cut into the flour 5 tablespoons of well chilled butter, cut into small pieces.
In small bowl:
1/2 cup plus 1 teaspoon buttermilk or plain keefer (if you don't have buttermilk, add 2 teaspoons of lemon juice or vinegar to the measure - fill with milk and let sit 10 minutes).
splash of vanilla
1 egg all whisked together
Combine wet and dry ingredients and mix just until holding together (will look very shaggy) and knead 10 times on a floured board. If the mixture looks too dry, add another teaspoon of liquid. Handle as little as possible or you WILL have a brick.
Pat out on pizza or cookie sheet sprayed with non stick spray until about 7-8 inches wide and about an inch high. Dip a serrated knife into flour and cut the scones into 8 to 12 pieces, depending on how small you want them (regular or mini) separating them slightly with the knife.
Bake in preheated 450 F. degree oven 15-17 minutes. (check and rotate at 12 minutes)
I knew evening supper would be fairly heavy so my third meal was a smoothie with a handful of spinach, 1/2 banana, a cup of berries and a cup of keefir with the usual cup of water and ice. That makes a LOT of smoothie for about 250 calories. I'll drink one glass as a meal and have the rest as a snack later with a little dish of baby carrots.
Dinner was a chicken and biscuit style casserole I made up. I replaced half of the chicken with steamed broccoli, used reduced fat cream of chicken soup, non fat sour cream, fat free soup stock, and replaced the buttermilk in the biscuit topping with 2% milk soured with lemon juice.
As for the portion size, I just sort of winged it to be about a cup of food. I went back and got a little more, but honestly, in the old days I would have filled my plate, so even with "seconds" I feel like I was improving.
As far as portion size - some folks recommend using the plate method ( a little less than 1/4 for protein, a little less than 1/4 for starch, a little more than half to be vegetables). I bought one of those plastic divided plates a while back to get an idea of how much is a serving.