Peel the cucumber, cut in half lengthwise, scrape out the seeds and roughly grate the cucumber halves. Mix with a little salt and leave to soak in water for about 15 minutes. Then squeeze lightly and add to the yogurt in a bowl.
Peel the garlic and add it finely or press it. Season to taste with salt and pepper. Cover and let steep in the refrigerator.
Wash and clean the broccoli, divide into florets, peel the stalk and cut into pieces. Boil everything together in salted water for 8-10 minutes until soft, drain, rinse, drain well, then mash lightly with a fork.
Mix the eggs with the flour, milk and cheese. Season with salt and pepper and mix in the broccoli.
Take portions of the mixture (about 2 tablespoons) and place in the hot oil in a large, coated frying pan. Flatten slightly and fry for 2-3 minutes until golden brown. Turn and finish frying for another 2-3 minutes until crispy.
Drain the broccoli pancakes on paper towels and serve with the tzatziki.