Belmont breakfast and/or coffee shop?
You have a few choices:
1. Andros Diner just a couple of blocks from Waverly Square on Trapelo (going towards Beaver Brook Reservation and McLean Hospital). Nice little diner. But I live in Watertown (6 blocks away) and I'd rather go to Deluxe Diner, Spot Cafe or Cafe Cakes in Watertown.
2. Vicki Lee's in Cushing Square (www.vickilees.com). I find VL's a little too expensive for my taste, especially just for a spot of coffee or breakfast.
3. Cafe D'Or just off of Cushing Square (442 Common St.). This is a cute little Lebanese place that serves up breakfast as well. The Lebanese food is very good, but I have yet to try the breakfast.
4. Select Cafe on School Street (283 School Street) going away from Waverly Square and McLean Hospital. This cafe has wonderful sandwiches on really nice baguettes, lovely omelettes and tasty quiches.
If you are willing to drive a few more blocks, Watertown has many breakfast offereings especially in Watertown Square. But I hope my suggestions suffice. Enjoy!