There's a collision of Philly street food and Mexican street food at the new Union Taco at 712 W. Girard Ave.

Chef Nick Farina has developed a cheesesteak taco, which he will introduce Thursday, Dec. 12.

The taco combines a house-made Whiz-like sauce made of gouda, provolone, American and pepper jack cheeses, with braised beef short rib, lettuce, tomato, onion and crimini mushrooms,  and topped with pickled jalapeno peppers stuffed with pork tenderloin and Mahon cheese and served on a house-made six inch flour tortilla.

Union Taco's tacos come two per order, so an order of two will cost $4 on Dec. 12 and $8 when they're not the shop's "$2 Taco Tuesday" feature.

It's also $7 as a torta and $10 atop a flatbread.