Well, I don't eat slimming foods/shakes, but I actually tend to eat a bit weirdly and it wouldn't suit everyone... I've just started a job where I stand most of the day, so I need food throughout the day, so on days where I'm working I'll have milk and cereal (with berries if we have any in) for breakfast, a sandwich and fruit for lunch and then something home-cooked for dinner, but I'll have more than 1,200 to play with as I use a FitBit and so will be awarded some exercise calories (although I only eat half of these back).
On days where I'm at home, and therefore only have 1,200 calories, I actually much prefer to skip breakfast (I hate forcing down breakfast, I'm not a fan of eating early in the mornings, but know I need it on days where I'm working otherwise I'll faint!) Then at lunch I'll have a small sandwich, (thinly sliced brown bread with Quorn chicken and some sort of chutney) and fruit. But the majority of my 1,200 calories I'll then use on dinner and an after dinner snack - say, pasta with tinned tomatoes, chopped peppers, onions and some meat, or a veg-packed homecooked curry. My evening meals can be around 700 calories this way, which doesn't work for everyone - I don't get very hungry in the day, but like a big homecooked meal with my partner in the evening. Then I'll have an after dinner snack of whatever I fancy, we tend to get Graze boxes which have lots of nuts/dried fruit etc and I quite often have some of those, or popcorn, fruit, sometimes chocolate if I fancy.
Because I eat most of my calories at the end of the day and don't snack (I've never been a snacker), I don't find 1,200 calories hard to work with, so it's easy to find a nutritional balance by adding lots of vegetables and protein to my big evening meal. Sorry if that's not very helpful, the myfitnesspal forums have lots of advice about spreading 1,200 across the day in a healthy way, which is definitely a more 'normal' way to eat, but doesn't work for me!