If you freeze meals in advance and don't have a microwave, you can pull the meal out the day before and let it defrost over night. Otherwise, if it is an air tight bag/container, you can submerge it in COOL water about 20 minutes per pound. Do not use hot/warm as the outside of the food will defrost too fast and allow bacteria to grow.
I do single serving roasts all the time. Use your meatloaf pan as your roaster so that the right amount of fluids, veggies build to the correct height in the pan.
For onions, I prepare them ahead. I dice some, shred some, chop some and put them each in their own ziplock bag and freeze them flattened out. When I need some, I break off a bit of the type of onion I need.
I use my toaster oven almost exclusively to cook everything - big savings on energy costs because there is less to heat and big savings on time because it doesn't take as long to heat up and I tend to need less cook time overall.
Stir-fry with is really quick, easy and healthy. I often use a vinaigrette
for flavor rather than sodium loaded Asian sauces
Veggie/meat loaded omelet
Pasta: one tomato pureed, garlic, onion, herbs, handful of pasta
Fish: grilled, foil wrapped, poached in water & lemon juice, baked, fried
Pork chop: cut a slit, stuff with pesto sauce or something else tasty, then bake
I still find salad fixings a challenge. I just can't get through a whole head of lettuce before it goes bad.
Those who think they have no time for a healthy lifestyle will sooner or later will have to find time for illness.