Six-year-old Sauce Restaurant on Rivington Street has converted part of its outdoor seating area into a takeout-pizza spot by repurposing one of the Allen Street side windows into a walk up slice joint.

"I always thought it would be fun to create some pizzas using some of the different sauces we use at Sauce," Sauce owner Adam Elzer tells Gothamist of his new pizza business LES Pizza. "Last summer we decided that we were gonna try to make the perfect New York City slice. We bought a pizza oven and started playing with different recipes and pizza chefs and going in after hours and making pizzas and testing things out."

The Sauce team visited places like Joe's Pizza on Carmine Street—"the best slice you can get," says Elzer—DiFara, Best Pizza and even L&B Spumoni Gardens to examine the architecture of their square pies. They veered away from brick and wood-burning oven pizza towards steel top, since they felt it was more in line with NYC slices. The experimental stage lasted nine months, after which Elzer and team felt confident enough with their creation—which at that point had morphed into a thin slice pizza—to bring their new baby to the public.

The amount of dough going into the crisp crusts is less than half of traditional pies, which Elzer thinks lets the sauces and cheeses really shine through. He's using his traditional restaurant's house sauces, including a chunky and garlicky "filetto" and a cream-based red sauce "mantecato" to make the base for the 10 different 19-inch pies the kitchen has created thus far. Each night they'll offer between four or five in slice or pie form, with the LES Classic with fresh mozzarella ($19/pie) and a Veggie Pizza made with a zucchini sauce ($28) always on offer. Slices are between $3 - $5.

"A traditional pizzeria probably just develops one sauce and they have to stick with it," Elzer says. "At our restaurant we're making all of these different sauces every night for our specials and for our pastas and we were able to alter these sauces a little bit and use them on pizzas, which is how we're creating a lot of our speciality pies."

Beginning on Wednesday, LES Pizza will be open in the evening serving slices and pies to go or for consuming at one of the stand-up tables out in front of the window. "Sauce is a neighborhood place so the window is meant to service the neighborhood," Elzer says. That means opening earlier and closing later than the restaurant proper, with plans for lunch sandwiches like a chicken parm and "Raguboy" (a meatball sandwich) soon.

78 Rivington Street, 212-420-7700; lespizzanyc.com. Open 5 p.m. Monday - Friday and noon on Saturdays and Sundays for now.