Method
1. Tip the lentils into a bowl, cover with cold water and set aside to soak for 15 mins. Fill and boil your kettle. Peel and finely chop the onion. Drizzle 1 tbsp olive oil into a medium-sized pan on medium heat. Add the onion, season with a pinch of salt and pepper and fry, stirring often, for 8-10 mins till golden brown and softened.
2. Drain the lentils and stir them into the onions with the ketchup. Pour in 600ml hot water from the kettle. Turn the heat up and bring to the boil. When it's boiling, turn the heat down, pop a lid on the pan and simmer for 10-15 min till the lentils are tender and have asborbed most of the water. They should be thick but still a little soupy.
3. Add the cumin and cayenne pepper to the lentils (the cayenne is hot, so add as much or as little as you prefer). Simmer, stirring, for 2 mins. Add the bulgar wheat and top the pan up with 250ml hot water from the kettle. Stir well to mix. Take the pan off the heat and cover with the lid. Leave to stand for 15 mins, till the bulgar wheat has absorbed the water and become tender.
4. While the bulgar soaks, finely grate the lemon zest into a mixing bowl and squeeze in the juice. Add 1 tbsp oil and the tahini and stir until you have a smooth sauce. Add the Greek style yogurt and ripple it through the sauce. Set to one side.
5. Trim the roots and ragged greens from the spring onions, then finely slice them. Finely chop the parsley leaves and stalks. Trim the tops off the peppers. Halve them and scoop out the seeds. Chop the peppers into thin strips.
6. Drizzle 1 tbsp olive oil into a frying pan on a medium- high heat. Add the sliced peppers and season with a pinch of salt and pepper. Fry, turning them occasionally, for 5 mins, till the peppers are tender and lightly charred. Transfer them to a serving dish.
7. Slice the root end off the romaine lettuces and separate the leaves. Arrange them on a large serving platter or individual serving plates.
8. Check the pan of bulgar wheat and lentils and drain off any excess water. Add the spring onions and most of the parsley to the pan (keep a pinch back for garnishing) with 1 tbsp olive oil and stir well to mix. Taste and add more salt, pepper and cayenne, if you think it needs it.
9. Scoop a tablespoon of the lentil and bulgar wheat mixture out of the pan and shape it into a long sausage-shaped köfte with your hands. Pop it into one of the lettuce leaves. Repeat till you have used up all the mixture and filled the lettuce leaves with lentil köftes. You should make around 16 köftes.
10. Add the cooked peppers to the koftes. Drizzle a little of the tahini yogurt sauce over each köfte. Garnish with chopped parsley and serve.
11. Get Ahead
You can make the lentil and bulgar mixture 4-5 hrs before you want to serve them and store it in the fridge. Take it out 30-45 mins before you want to serve the köftes. You can also serve the lentil mix in a bowl, with the yogurt sauce in a separate bowl and the lettuce leaves on platters so people can scoop and make their own köftes at the table.
12. Love Your Leftovers
The lentil köftes will keep for up to 1 day in the fridge and are best served cold. Store them in an airtight tub, with the yogurt sauce in a separate tub.