Put all the ingredients for the falafel, except the flour and oil, in the bowl of a food processor. Season with salt and pepper, then process into a rough paste. Using slightly wet hands, divide the mixture into 8 equal-sized balls, flattening them a little to make burgers. Cover and chill for 30 minutes.
Mix together the yogurt, mint and garlic in a small bowl. Season with salt and pepper, and set aside until needed.
Coat the chilled falafel burgers lightly with the gram or plain flour. Pour just enough oil for shallow-frying into a heavy frying pan over a medium-high heat. When the oil is hot, carefully add the falafel burgers and fry for 4 minutes on each side until golden brown and crisp.
Toast the pitta breads under a preheated hot grill until warmed through but still soft. Spread each one with some hummus and top with the salad and a burger. Sprinkle with a little paprika, and serve immediately with the garlic mint sauce for spooning over the top.