Heat your oven to 200ºC/Fan 180ºC/Gas 6. Wrap the bulb of garlic in foil. Pop it in the oven and roast for 30 mins till it’s fairly soft.
While the garlic roasts, peel the beetroot. Coarsely grate them. Tip them into a food processor. This step will be messy - you might want to wear gloves and an apron.
Drain and rinse the chickpeas. Add them to the processor with the flour, 1 tsp of the ground cumin and the sachet of sesame seeds. Season. Blitz to make a chunky paste. Fill a kettle and boil it.
Shape the mixture into 8-10 rounds. Grease a baking tray with ½ tbsp oil. Pop the falafels on the tray. Bake for 40 mins. Flip once while they’re baking so they’re golden all over.
Pop the couscous in a bowl. Pour 250ml hot water from the kettle over the couscous. Cover with a saucer or some cling film. Leave to one side to soak up the water.
Peel and finely slice the onion. Halve or quarter the tomatoes so they're roughly the same size.
Pop all the salad ingredients into a bowl. Juice half the lemon. Whisk with 1 tbsp olive oil and some seasoning. Drizzle over the salad.
Unwrap the garlic and separate the cloves. Slice off the bottoms and tips. Squeeze them out of their skins. Crush them and mix with the mayo. Season. Serve the falafels with the couscous, salad and the roast garlic mayo.