1. Fit a large Dutch oven with a candy thermometer and fill halfway with vegetable oil. Heat over high heat until the oil reaches 325º. Adjust the heat as needed to maintain this temperature throughout the cooking process. 
2. Heat a large skillet over medium heat. Add the olive oil and ground lamb. Cook, breaking up the lamb with a wooden spoon, until no pink remains, 4 to 5 minutes. Transfer the lamb to a paper towel-lined plate. Wipe the skillet clean. 
3. Add the onion and peppers to the skillet and cook, stirring often, until the vegetables are tender and starting to brown, 8 to 10 minutes.
4. Return the lamb to the pan and add the salt, paprika, and cumin. Stir to combine.
5. Transfer the filling to a shallow sheet pan and refrigerate until cool, 10 minutes. 
6. Unroll the puff pastry sheets. Using a sharp knife, cut each sheet in half lengthwise. Cover with a damp towel until ready to use. 
7. Place one puff pastry strip on a work surface. Place 2 tablespoons of the filling about 1” from the bottom of the strip. Fold the left bottom corner of the puff pastry strip over the filling to tightly enclose it and form a triangle. Continue folding the triangle, flipping right and then left until you reach the end of the strip. Use a sharp knife or scissors to trim any excess puff pastry. Repeat with remaining puff pastry strips and filling. Transfer the folded briouats to a tray and cover loosely with a damp towel until ready to fry. 
8. Working in batches of 2 to 3, gently drop the briouats into the frying oil. Fry until golden brown and crispy, 8 to 10 minutes. Transfer to a paper towel-lined plate. 
9. Serve the briouats with Greek yogurt, parsley, and mint. 

Recipe adapted from: Serious Eats