Definitely like to cook something new whenever I’m either just a little hungry or I can eat while I’m cooking. For example, I tried making a mango salsa the other day and was able to snack on the mango while I was slicing everything else.
Also depends how big the new thing is though. If I’m attempting a whole new dinner recipe, I’d almost rather make it in the middle of the day when I’m not hungry at all and definitely am not ready to eat dinner. Lots of time to both clean up a disaster and fix something different for dinner without being hangry. But something small and easily replaceable, or doesn’t have a ton of cleanup? Whatever. Any times fine for that.
A lot of people have already commented, but let me add to the masses: soup with frozen veggies can be a total life saver. I was just sick and tossed in basically my whole freezers worth of frozen veggies over the last two weeks. I like to do some meal prep when I’m feeling good and freeze some of my better veggies, but I had bags of corn, squash and sweet potatoes and made chili out of it. Just chucked the whole bag frozen solid into the mix and cooked till it was thawed. I’ve done the same for smoothies when I’ve got some left over bits to use up. But I like green smoothies a lot, so I’m not sure that helps the average cook.
I’d add casseroles work well with some frozen veggies as well, but you have to be weary of the water content. Other than those three, I don’t think I’d use most frozen veggies for anything else. Maybe edamame with stir fry, but I can’t think of any other exception. Too mushy/watery.