Samosadilla

1 large yellow onion, diced
3 cloves finely chopped garlic
1 minced Serrano chile (green chilli)
1 1/2 teaspoons finely chopped fresh ginger
1 teaspoon kosher salt plus more to taste
1 1/2 teaspoon garam masala
1 teaspoon ground cumin
1/2 teaspoon ground corinader
1/2 teaspoon turmeric            
1/4 teaspoon cayenne
3/4cup green peas
700g cubed potatoes, cooked until tender in salted water
2 tablespoons chopped cilantro
juice from 1/2 lemon
salt to taste once mixed

For the Cilantro Lime Chutney Sauce:
 
1 large or 2 small bunches fresh cilantro
1/3 cup fresh picked mint leaves
1/4 cup sliced green onions
1 sliced Serrano chile
1 or 2 limes, juiced
1/2 cup plain yogurt
pinch of salt, optional