$4 for 2lb ground beef
$3 for 10lb russett potatoes
$4 for four apples
$4 for a 52oz jug of OJ
$18 total for ~8 "Happy Meal equivalents", or $2.25 per meal, so less than the actual Happy Meal, but you need 1. $20 cash to buy the supplies and 2. the time/equipment/knowledge to prepare the meals.
Yes, the headlines are rage-bait, but fast food is still ridiculously inexpensive. Yes, you ca reproduce the fast food at home, or live on rice+beans, for less. But add some quality protein and a pile of fresh veg and the price goes up.