What it means
A dollop is a nice hefty blob of something soft, dropped on with more vibes than precision. Think cream, mash, yoghurt, gravy, whatever's scoopable and not trying to look fancy. It's usually a bit generous, a bit wonky, and exactly the right amount if you're feeding people with proper comfort in mind.
Usage examples
"Just a small dollop of cream for me, she said, then accepted a mound you could ski down."
"A dollop of mustard, a dollop of mayo, and the sandwich was more sauce than filling by the end."
"He topped the crumble with such a huge dollop of custard that it slid straight off the side of the bowl."
"Give it a dollop of sour cream and stop pretending we're doing tiny fancy portions."
"She said just a dollop of gravy, then absolutely baptized the roast in the stuff."
Where it comes from
Dollop goes back to an older English dialect word for a lump or clump, often something uneven left sitting in a rough shape. That sense of a chunky little mass slid neatly into food talk, so a dollop came to mean a spooned-on blob of something soft, with no fussy measuring involved.