The Best Single-Subject Restaurants

First it was burgers, then it was pizza, and now there are many restaurants around the country devoted one great ingredient beyond the usuals. These single-subject eateries reinvent simple recipes and create a slew of savory and sweet creations that you'll want to eat all the time. From bacon to grilled cheese, read on and you'll find your favorite food has its very own dedicated restaurant.

Ahhh, grilled cheese. It's the quintessential American sandwich we all loved as kids and...still do. Jonathan Kaplan (founder of Flip Video) thinks we're enamored by it so much that he's launching 500 locations of The Melt, a high-tech grilled cheese-focused restaurant. The first is slated to open this August in San Francisco, but he's not the only player in the Bay area to put this perfect sandwich on a pedestal. The American Grilled Cheese Kitchen currently touts six iterations with additional specials each day, but the cheesiest is most definitely the "Mouse Trap" — a triple threat oozing with Cheddar, Havarti, and Monterey Jack.

Is San Francisco too far to go? Check out Maryland's Grilled Cheese & Co. and Chedd's Gourmet Grilled Cheese in Sioux Falls, South Dakota, and Austin, Texas.

Try these versions tonight: 10 Swoon-Worthy Grilled Cheese Sandwiches.

If you've ever been to Italy, you may have sampled a sandwich stuffed with perfectly roasted pork from a whole roasted pig. Expert chef Sarah Jenkins decided that was the singular Italian street food she wanted to offer New Yorkers. Her restaurant, aptly named Porchetta (pronounced por-ketta), features a sandwich with succulent, meltingly tender, moist roast pork loin topped off with chunks of the rich and fatty belly and crispy cracklings, distinguishing it from any other run-of-the-mill sandwich. Tip: If you want to forgo the bread get the porchetta plate. It's pork perfection.

Try these supreme sandwiches tonight: Fresh Twists: Celebrity Chefs' Spin on Sandwiches.

Bacon is the only focus at this single-ingredient food truck, Lardon (which translates to bacon in French). They have taken the cured meat to new heights, replacing taco shells with bacon and stuffing a bacon "shell" with sauteed potatoes and Cheddar. And, of course, there is no reason not to top a fudgy brownie with a bacon-Nutella spread and bits of crispy, smoky, strips of what else? More bacon!

Eat some bacon tonight: Salty, Smoky, and Sweet: 15 Top Bacon Recipes.

Whether at a baseball game or backyard barbecue, summer cannot be considered summer without eating a few hot dogs. But while we love a good street-cart frank or charred wiener from the stadium, these frank-centric spots have dog designs that definitely deserve a bite.

Austin, TX: Frank's Texalina — a locally produced pork and beef sausage topped with grilled coleslaw, Carolina mustard BBQ sauce, and white Cheddar cheese.

New York, NY: Crif Dogs's Spicy Red Neck — a bacon-wrapped frankfurter topped with chili, coleslaw, and jalapeños.

Brooklyn, NY: Bark Hot Dogs Classic pan-griddled featuring their own private-label dog.

Fairfield, CT: Super Duper Weenie's smoky New Englander — sauerkraut, bacon, mustard, sweet relish, and raw onion.

Chicago, IL: Hot Doug's Chicago-style — all-beef frankfurter cushioned by a poppy seed bun and topped with chopped white onions, sweet pickle relish, dill pickles, tomatoes, sport peppers, and yellow mustard.

Try these versions tonight: Totally Tubular: Hot Dog Recipes and Toppings.

Some call it the best food on Earth, and there's no denying that without mac 'n cheese, many kids (and parents) would find it hard to survive on the planet. Though once a simple concept (butter, flour, milk, cheese, and elbow noodles), it has cleverly been re-invented into oodles of versions. A few favorites include: Macbar's decadent mac lobsta' (pictured) — fresh lobster meat, cognac, tarragon, and mascarpone — and Homeroom's funky and fun Trailer Mac — a bowl of Cheddar mac filled with Niman Ranch hot dog and topped with crushed potato chips. Holy mac!

What do we like best about meatballs and spaghetti? The meatballs, of course! That's exactly what co-owners Dan Holzman and Michael Chernow thought when they conceived The Meatball Shop, a popular downtown Manhattan restaurant. There, diners feast on five varieties of meatballs, from veggie to the specialty of the day, all mixed and matched with a choice of sauces. One of their latest creations: The Reuben-Corned Beef ball with Swiss cheese, caraway seeds, Thousand Island dressing, and sauerkraut. Finish it all off with an ice cream sandwich, also with customizable flavors for both the cookie and the ice cream.

The Meatball Shop is soon to be in two more outposts in New York City and, with any luck, they may be coming to a location near you.

It's summer and that means it's prime season for lobster rolls on the North Eastern shore. Haven't had one? Well, you're certainly missing out. The classic formula begins with a New England-style soft hot dog bun, toasted and painted with butter then piled with tender, chilled lobster meat that's lightly tossed in a mayo-based dressing with some chopped celery and seasoning. It is a summer sandwich worth saving up for and that's now available year round from single-subject shops like Luke's Lobster in Washington, DC (and several locations in New York City) and as of this August, at Las Vegas's Lobster ME (photographed).

Try making a lobster this weekend: DIY Luxury: Backyard Grilled Lobster Menu.

Los Angeles's Würstkuche has a cure for those who are sausage-obsessed. Their more than 20 artisanal wurst sandwiches are served on a freshly baked rolls and can be topped with your choice of caramelized onions, sauerkraut, spicy peppers, or sweet peppers. The sausages range from the classic German Bratwurst (pork sausage seasoned with coriander and nutmeg) to the more daring: rattlesnake and rabbit with jalapeños. (We'll take the former.) The drink menu is fairly extensive, as well,t offering well-crafted sodas, a wine list and Belgian, German, and American brews from Trappist ale to a raspberry lambic.

12 Irresistible Waffle Recipes

We've saved the best for last. Peanut butter and jelly never gets old at PB&U in suburban Philly. Let's start with Exhibit A. Peanut butter. Check. Nutella. Check. Marshmallow Fluff. Check. And the kicker? Your choice of chocolate chips or mini m&ms. We wish this place was around when we were kids.

If you're not near the city of Brotherly Love, but near New York, check out Peanut Butter & Co. where you can savor The Elvis: a steamy hot grilled peanut butter sandwich with bananas, honey, and bacon!

Try these peanut butter creations: 15 Perfect Peanut Butter Desserts.