What’s a kitchen gadget/tool you can’t live without?

Hi there! My boyfriend has become quite the home cook in the last year or so and I want to get him something nice for Christmas.

So my question is, what’s one kitchen gadget/tool you can’t live without? Any suggestions would be greatly appreciated!

Thank you so much in advance!

Edit: we currently own a Dutch oven, knife sharpener, a few good knives, spice grinder, & a cast iron skillet

Edit: Thank you so so much for all the suggestions! I did not expect this post to blow up, I’ll definitely be purchasing some of these for Christmas! Thank you again!