In a medium saucepan, add lentils, stock and 1 teaspoon of olive oil. The olive oil with help reduce foam build up when lentils are cooking. Bring to the boil then reduce to a simmer and cover with a lid. Cook for 15 minutes or until lentils are cooked.
In a small saucepan, heat 1 teaspoon olive oil and sauté onions on a very low heat for 10 minutes. Add this to the cooked lentils along with the tomato paste. Cook for a further 2 minutes. Remove from heat and add breadcrumbs. Mix to combine. With wet hands, shape into 5-6cm patties that are 1½ -2cm thick.
To cook, lightly oil a frypan and cook patties until golden on each side.
Serve with steamed rice and vegetables or make a burger with salad and your favourite sauce.
Freeze any uncooked patties separating them with baking paper as you store them.