The flaky rectangles encase mostly fruity fillings. They’re often crimped at the edges, always slicked with icing, and decorated with sprinkles or drizzled with stripes. Across the board, they outshine their mass-produced counterparts in taste and texture. That’s right: Pop-tarts have gone handmade in Philly.

At Green Engine Coffee Co. in Haverford, they’re sleek and sophisticated, with flavors like fig-apple-rosemary, matcha-mojito with candied lime, and rhubarb-tehina-pistachio. Straightforward fillings (blueberry, strawberry) reign supreme at Bakeshop on 20th in Rittenhouse Square, where each tart is the size of sheet pan, sold whole or sliced up.

At Crust Vegan Bakery in Manayunk, there are originals (lemon-lavender, fluffernutter) and riffs on the classics (wild berry, brown sugar-cinnamon). And inside the Reading Terminal Market, at Molly Malloy’s, they’re fork-and-knife affairs both sweet and savory: salted caramel-apple, strawberry-champagne, potato-leek, even Thanksgiving (a turkey, stuffing, mashed potato, and cranberry filling topped with a gravy drizzle).

“People haven’t quite come around fully to the idea of savory ones. We have a lot we want to do, but we try to introduce them every now and then,” says Miranda Cauley, special projects coordinator for Iovine Brothers Produce.

Cauley collaborates with Molly Malloy’s, where she and chef Bobby Fisher schemed on ways to incorporate more of Iovine’s local produce into the pub’s menu. Fisher had never made a pop-tart, but he loves making fresh jams and tried folding some into a modified version of his potpie pastry crust. Happily, it all came together in one go.

“Luck was on our side that day,” Fisher says.

Thus was a born a new specialty for Molly Malloy’s. Since August, the restaurant has featured weekly tarts filled with seasonal fruit fillings: peach, apple-pomegranate, mango, key lime.

“We’ve never done these through the spring and summer, so we can’t wait” for the coming seasonal produce, Cauley says. “We’re both personally very excited for like strawberry-rhubarb and cherry.”

The pop-tart inspiration was more nostalgia-driven at Green Engine Coffee Co., where owner Zach Morris nudged chef Kelsey Bush to try her hand at them in 2017. “We had just made the change to start baking, and I am not a baker,” Bush recalls. “I did not want to learn how to bread-bake. I did not want to learn anything too, too difficult, but he was like, ‘I want to do pop-tarts.’”

Through trial and error, Bush came up with Green Engine’s recipe. She unknowingly laminated the dough — a method of incorporating butter so that the dough bakes up in extremely flaky, croissant-like layers. “Now, working with my French pastry chef [Sofiane Bellal] at Bloomsday, he’s showing me how to do all this stuff and I was like, ‘Oh yeah …,’” she laughs. “It’s a very labor-intensive thing.”

Bloomsday, Green Engine’s sister operation, has become baking central for both locations during the pandemic, so Bellal now heads up pop-tart production. Though he’s come around on them in general, the trademark bright colors of the breakfast treat can be a little confounding.

“Bright colors are not Sofiane’s thing. He’s traditionally French, so it’s very much neutral colors, beautiful things. And I’m like, ‘Sofiane, make it blue.’”

Bloomsday and Green Engine’s pop-tart dough is made with Castle Valley Mills spelt flour (for a toasty flavor) and high-quality butter; the two layers are pinched shut with a fork and sealed with an egg wash. The fillings often harness leftover fruit and cocktail syrups. “I’ve also been able to throw in herbs, like [candied] rosemary,” Bush says. “It is such a great way to waste-stream things.”

Green Engine influenced pop-tart aficionado Erika Burke, who scoped them out, along with other local iterations, last year when she developed her own recipe for a fund-raising drive for Girl Up, an initiative to promote women leadership. Head baker at Essen on East Passyunk Avenue, Burke has been perfecting them ever since — try one at Essen on the weekends — and branched out into a pop-up operation called Flaky.af, making appearances at Herman’s Coffee, Hey Rally, and Somerset Splits.

Burke channels the most nostalgia of any pop-tart maker in town, making liberal use of sprinkles and colorful stripes. She’s tackled not just fruity fillings (wild berry, blackberry, guava), but also dessert-driven flavors like banana split, chocolate-peppermint, and raspberry cheesecake. Her cookies-and-cream pop-tart would be a dead ringer for the original if not for its height. Making chocolate dough was trickier, she says, because the cocoa powder changed the fat ratio, but she was determined. “It took me a couple tries to get it right, but I finally got it.”

Since launching Flaky.af’s Instagram account last July, Burke has had several prospective customers ask whether she ships. She’s not sure that would ever be possible given how buttery her dough is. Unlike the foil-wrapped Kellogg’s Pop Tarts a school-aged Burke used to keep in her backpack, her version is not something she recommends eating on the go.

“You need a plate for these pop-tarts.”

Where to get a handmade pop-tart:

Bakeshop on 20th: $5.50 Available on weekends, 269 S. 20th St., 215-644-9714, bakeshopon20th.com

Bloomsday: $5. Available on weekends, 414 S. Second St., 267-319-8018, bloomsdaycafe.com

Crust Vegan Bakery: $6. Available as supplies last Wednesday through Sunday; 4409 Main St., (215) 532-7867, crustveganbakery.com

Essen Bakery: Two for $12. Available on weekends, 1437 E. Passyunk Ave., 215-271-2299, essenbakery.com

Green Engine Coffee Co.: $5. Wednesday through Sunday, 16 Haverford Station Rd., Haverford, 484-416-6164, greenenginecoffee.com

Molly Malloy’s: $6. Available daily; Reading Terminal Market, 1136 Arch St., 267-525-1001, mollymalloysphilly.com