I usually plan one week in advance. We try to get to the fishmongers on Fri/Sat for a nice meal on Saturday. We love love love fish and will treat ourselves once a week w/ something really nice.
The usual suspects are:
Chili
Chicken Noodle soup
Roast chicken
Thai sweet chili chicken salad (if I have any chicken left over from the roasted chick)
Chorizo spaghetti
Beef stew
Portuguese chicken and rice
cottage/shepard pie
fish pie (our current favorite!!)
spaghetti bol
proscuitto wrapped monkfish
roasted cod w/ cherry toms
I also try a new recipe every couple of weeks. I might just be a different recipe of a staple like a new beef stew recipe. I tend to try new fish recipes because my fishmonger is ace and will prepare the fish just as I need it ( I don't know if they're all like this as I only have experience with this one so not to offend any other fishmongers out there) so I don't have to fiddle with it once I'm home. As for fresh veg unless I'm going to use it in the first 2 days I don't buy it. I find that veg goes off fast here and I used to waste A LOT so I will pop out for the fresh ingredients- luckily I have both a Tesco express and a Sommerfields around the corner as well as small Asian green grocers.
Being a SAHM I have LOADS of time to think and plan dinner- it's kind of what I do!!
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I was never this organized when I worked so hats off to those of you that work outside the home and cook everyday!! Being the lazy sod that I am I used to have ready meals/takeaways a lot!!