If you want a quick lunch and are in the mood for a good burger, try Reggie's Hot Grill at 89 Hunter St E http://reggieshotgrill.ca/ . It has burgers with tons of different toppings, and free fried onions. My friend had a chicken burger that was huge and fresh cut onion rings. It was featured on You Gotta Eat Here on the Food Network. Worth a stop!
Have not lived there in 5 years, but when I go back for visits I frequent these spots:
-St. Veronus, it's a Belgium trappest restaurant. Amazing beer selection and good food with good portions.
- Black Honey Cafe and Bakery, amazing desserts and pastries. Fair trade coffee and a great atmosphere, go after dinner or for Sunday brunch!
- Sam's Deli, really amazing sandwiches. period.
-Rare Steakhouse, I'm sure the name gives away the focus of the menu. A first where I've seen a restaurant focus on local and seasonal in Peterborough (aside from Black Honey), reasonable prices and good wine list.
-The Planet Bakery, great for lunch or brunch.
- Curry Village, fantastic indian. These guys know what they are doing and have been insanely successful in Peterborough.
-The Night kitchen, I dream of their thin crust pizza all the time. When stumbling over there after a few pints at The Only your selection is limited, try to get there early or go when it's not 2 am.
-Karma's Cafe, Good thai food and a nice patio.
- Purvey's Fish and Chips, the best Peterborough has to offer.
If you find any amazing spots, please share!
ktbee24 has it summed it up fairly well. I would add the following:
- Black Honey does have an excellent weekend brunch selection. However, it is sometimes hit or miss. I'm not sure whether it's because the cook changes or if quality goes down later in the day. It's just that sometimes the eggs can be overcooked or the potatoes a bit cold. That's being picky because even a "miss" is pretty good. It's definitely more than your typical breakfast place.
- If looking for more of a typical bacon'n'eggs place then I would recommend the Monaghan Cafe. Their benedict is delicious.
- Elements at King and Water was very tasty - though pricey - the one time I went there. Spanish and Portuguese influenced including tapas.
- There's a new place, Kettle Drums, on the corner of Aylmer and Hunter. I've been their twice now for pizza and it really is some of the best pizza I've ever had. Great wood-oven pies with perfectly crisp crust and loads of cheese. The toppings aren't too adventurous but extremely tasty. I would go for the gorgonzola-fig pizza or the four meat pizza. It's in a completely different league than The Night Kitchen, though only the latter does slices.
- The old stand bys are the sister restaurants of the Old Stone and Hot Belly Mama's. They're both very lively, have a good selection for a variety of palettes, and are fairly decent for quality and value. Nothing mind-blowing but they'll do for non-discerning eaters. They brew their own beer, which I would put in the above average category.
- If the weather is nice, nothing is more summery than the patio at the Only. They have very tasty grilled sandwiches, mostly based around the turkey they roast fresh every day.
Addendum: St. Veronus opened Le Petit Bar, a charcuterie and wine bar, next door to the main restaurant. It's quite good with a nice selection of cheeses from Ontario, Québec, and France, though, truth be told, I'm no expert in these matters. It is a nice option if you're looking for something light, as would be the tapas menu at Elements.