The worst part, for me, is the actual "It's 5pm and DD is saying Ummies, Ummies, the oven is cold, and the fridge is bare" moment. DH works late most nights, so dinner is frequently just me and 2YO DD. I try to be rather thrifty, organic, local, homemade.
South Mountain delivers on Fridays (that's our day, not everyone's day). Our cutoff for orders is midnight Wed. So by COB Wed I have a rough idea of the following week's needs for milk, butter, eggs, yogurt, meat, etc.
I grocery shop at WF on Saturday AM's. Every now and then I will send DH to the store on his day off, but he tends to ignore the list and come back with ice cream and soda ("but I couldn't FIND the celery..." lol).
I use the crockpot frequently and make monster portions, then freeze soup, stew, chili, etc for later use. This is good for leftover lunches at work as well.
For example, the upcoming week (this is just dinner):
S: hamburgers, broccoli
S: fish, sauteed spinach
M: just me and DD, probably scrambled eggs, peas, and toast
T: beef fajitas
W: pizza quesadillas with marinara dipping sauce (cheese, pepperoni, spinach), fruit
T: just me and DD = leftovers
F: just me and DD = no idea yet, but in all honesty, probably fruit and yogurt smoothies or scrambled eggs again.
This morning, SMC delivered milk, eggs, yogurt for next week. I sent DH to the store for tomato paste and crushed tomatoes. The hamburgers and beef for fajitas are frozen. I have salsa, rolls, and will make the tortillas and marinara at night after DD is asleep.
Tomorrow at WF: fruit, broccoli, spinach, peppers and onions, shredded mozzarella, pepperoni, and whatever fish/seafood looks good and doesn't require a 3rd mortgage.
Granted - this kind of menu assumes a certain level of stocked pantry and ability to "just throw things together" I do not mess with old el paso taco/fajita/whatnot kits.
Not this week, but many weeks I will do a large crockpot meal on the weekends when I can set it up during DD's breakfast (I leave REALLY early). The meals during the week are super, super quick prep, ie making quesadillas is not complicated and also does not create 1,303 pots and pans and bowls to wash. I hate that.
I am a big fan of cook once, eat twice (or 3, or 4). Ie roast a chicken and eat several meals off of it. Chicken salad is fast! I often put a chicken in the oven right before taking DD upstairs for a bath/bedtime. I know I won't be gone TOO long lol, I'll still have time to clean up after, and then we have a tasty and easy source of protein for several meals

Those fajitas? I will make the tortillas, marinate the meat, and cut the peppers and onions the night before. So once I get home from work it's just drop and stir... like a cooking show.
I found once DD was mobile, cooking became harder. Now that she is older and can stand on a stool at the end of a counter and"help" mom (ie tear lettuce with her hands) it is easier to make dinner. If she starts whining that she is hungry, I usually give her fruit or veg to snack on... that way, if she fills up before dinner, hey, no problem. OR... i will give her whatever I think she will like LEAST. If she's really hungry she'll eat it, but also make room for spaghetti in 10 mins.
Also, we fully embrace breakfast for dinner, yogur and fruit smoothies for dinner, and cheese and crackers and fruit for dinner. Hey, it's balanced and it's not every night. Beats the golden arches.