Heat a large skillet over medium heat. Add ground beef, onion, and garlic; cook until beef is browned and crumbly, 5 to 7 minutes. Reduce heat to low.
Mix in coriander, cumin, salt, turmeric, chile powder, and ginger. Add peas and water; bring to boil. Cover and simmer, stirring occasionally, about 25 minutes. Uncover and cook over medium heat, stirring frequently, until any remaining liquid evaporates.
Stir jalapenos and garam masala into the beef mixture. Remove from heat and stir in lemon juice; let cool until safe to handle, at least 15 minutes.
Drop about 1 tablespoon of the beef mixture onto the center of a wonton wrapper. Moisten edges with water, fold them over the filling, and seal. Repeat with remaining filling and wonton wrappers.
Heat about 1/2 inch oil in a large saucepan over medium-high heat. Add samosas in batches; fry until browned, 1 to 2 inches per side.