Designing Kitchens and Bathrooms - new bathroom sink - gaps in corner

I just put in a new integrated sink/counter in a small half bath. The counter fits from one side wall to the other side wall, and I ordered it about 1/2 to 3/4 inch smaller than the actual space to be sure I could fit it between the walls. But now after I put up the 4 inch sidewalls on each side (there was a built in 4 inch backsplash), I have almost a 1/2 inch square gap in the 2 back corners, between the backsplash, sidesplashes and walls. It looks like it is too large of a gap to fill with caulking. Is there anything anyone knows of I can use to fill the gap? The sink/counter are made of a solid-surface material.

marys235,

You have options which could look good to hide the mistakes;

1. Obtain some polystyrene paint process finish moulding to fit atop the backsplashes, glue and paint. Just to install on the sides.

2. Obtain a Square Corner Block to add some detail 5/8" x 2 1/2".
Placing one on each side glue and paint or stain.

Check out Home Depot on Moulding and Blocks.

Hope this helps!

Thanks, Doug, I'll give those things a try. I appreciate the help!