I can’t think of a better pitch for a restaurant concept than “gourmet-level pizza on a waterfront cafe,” and this summer there are two Chicago restaurants that fit that description: Pizzeria Portofino, the Lettuce Entertain You concept hugging the north bank of the Chicago River, and Robert’s Pizza & Dough Co., an independent operation overlooking Ogden Slip in Streeterville.

Both appear to have bright futures, so let’s take a look at each one.

Pizzeria Portofino

Lettuce Entertain You’s latest pizzeria has been wildly successful. On sunny days (and there have been a ton of them since Portofino’s July 1 debut), the restaurant is jam-packed from noon to last call.

Reservations, available through Tock, get snapped up quickly; a quick search online turned up a few tables at 2:45 p.m., or 9:30 p.m. and later. Your options are to pick a date six weeks out and pray for good weather, or take your chances as a walk-in party.

Which is what I tried on my first visit, rolling in around 6 p.m. one Saturday. The hostess explained the dining room was fully committed, and frankly (but politely) said my chances of being seated were virtually nil. Undaunted, my wife and I headed for the bar, eventually staked out a little stand-up real estate, and had dinner that way. Which, on a sunny evening, was pretty pleasant.

Everything about the place is pleasant, really. Walking down the stone (well, concrete) steps from the Clark Street bridge to the restaurant immediately takes one out of the “I’m in Chicago” mindset. The open-air interior is done in stone and natural wood and includes an artificial arbor at ceiling height; servers are clad in white pants and navy-striped shirts. Sitting on (or gazing across) the patio and its white-wicker seating, watching the expensive yachts mosey along the water, and the Italian-Riveria effect is complete. Beyond the water is Chicago’s bustling Riverwalk, and the city skyscrapers loom just beyond that. There isn’t an unattractive view anywhere.

The challenge for previous occupants of the space (Bridge House Tavern most recently) is drawing customers during the many months that outdoor dining is impractical, if not impossible. Portofino intends to add awnings and space heaters to extend the outdoor season, but ultimately it will come down to the food, and Portofino does extremely well on that score.

Executive chef Doug Psaltis is in charge; I’ve practically lost count of how many Lettuce projects this jack-of-all-cuisines oversees (he’s the P in any RPM restaurant, for instance, including RPM on the Water, which will open above Portofino in a month or so), but he seems to be having a lot of fun with this menu, particularly the pizzas.

If pizza determines whether the restaurant rises (heh) or falls, Portofino will be in good shape. Psaltis’ pies have thin, light and crispy crusts, and the heels, aggressively charred by the wood grill, deliver a satisfying chew. The pizzas “have all the respect for Neapolitan pizza with none of the rules,” in Psaltis’ words.

Pies to try include the charred pepperoni, which has a lively but not overbearing spice presence, and the Pugliese with fennel sausage, rapini and pecorino. But the best thin-crust creation might not be a pizza at all; the foccacia, a Ligurian-style creation of super-light dough stuffed with stracchino cheese (“Italian cream cheese on steroids,” Psaltis calls it) is an addictive creation, suitable as a shareable snack. The focaccia name will confuse those accustomed to the more common, spongy bread, but they’ll love the taste.

For those who don’t dine on pizza alone, Pizzeria Portofino has plenty of pleasant distractions. Spicy tuna bruschetta is a nice appetizer mashup, and the watermelon and feta salad, bolstered by red onion, grape tomatoes and torn basil, is a refreshing starter. Pastas, in half and whole portions, include classic cacio e pepe, albeit one with a four-peppercorn blend, and trofie noodles with pesto. Among the grilled seafood, the delicious whole baby octopus serves as a fine entree and a strong hint that RPM on the Water will be worth our attention when it opens.

Spot-on service is a big plus, and the beverage program offers interesting cocktails and spritzes, and an all-Italian (a few Champagnes excepted), treasure-filled wine list by Richard Hanauer. One caution: The only chardonnay on the by-the-glass list (there are plenty of other options) is a premium pour for $27 — about double the price of the other wines on the list. It’s a delicious wine, but if you’re the sort of person who breezily orders chardonnay without so much as a glance at the menu, you’ll be in for a surprise.

Pizzeria Portofino

317 N. Clark St.

312-900-9018

Tribune rating: Three stars

Open: Lunch and dinner daily; brunch weekends

Prices: Pizzas and pastas $15-$22

Noise: Conversation-challenged

Other: Cash-free