Bring a medium saucepan of lightly salted water to a boil. Stir in potatoes and peas; cook until potatoes are tender but still firm, about 15 minutes. Drain, mash together, and set aside.
Meanwhile, heat 2 tablespoons oil in a large saucepan over medium-high heat. Add cumin seeds and bay leaf; stir until fragrant and seeds are browned. Add ground beef and onions; cook until beef is browned and crumbly and onions are soft, about 5 to 7 minutes.
Stir in garlic and ginger. Season with salt, cumin, coriander, turmeric, chili powder, cinnamon, cardamom, and black pepper. Stir in the mashed potato mixture. Remove from heat and chill in the refrigerator for 1 hour, or until cool.
Heat 1 quart of oil in a deep saucepan over medium heat.
Mix cilantro and green chile peppers into potato and beef mixture. Place approximately 1 tablespoon of the mixture onto each phyllo sheet. Fold sheets into triangles, pressing edges together with moistened fingers.
Lower samosas carefully into the hot oil in batches. Fry until golden brown, about 3 minutes. Transfer to a paper towel-lined plate to drain. Repeat with remaining samosas. Serve warm.
