I would have used the subway tile with a bull nose.

Corian makes an excellent window sill. Far superior to wood and tile.

Just plain white sill from any place the piece you want in the counter material is not happening so move on.

Cool space. NYC? How does stacking the dw work?

The thing is, you need a piece of solid surface, you don’t need it to match your counter. It could easily be white or black. I agree with eld it should have been done with bullnose tile, but so should the tiles on the side of the window ledge. If you didn’t do it there, I’m going to guess that tile doesn’t have a bullnose or trim. A piece of marble would also be fine if you have marble sills in the rest of the home.

Thanks for the responses. It is actually an ADU in L.A. My goal was to make the sill a little deeper that is why I didn’t use subway originally with bullnose. I will look into Corian and possibly tile options as it doesn’t look like I will find the quartz to match.