Pour the chickpeas into a sieve, rinse cold and drain well. Rinse sprouts and drain. Remove the pistachios from their shells and chop roughly. Peel garlic, also chop coarsely. Squeeze lemon. Halve avocados, remove seeds and peel the flesh.
Puree chickpeas, avocados, lemon juice, pistachios, garlic, tahini and oil with a hand blender. Season to taste with salt, pepper and sugar.
Clean and wash the radishes and cut them into fine slices. Arrange dip with sprouts and radishes.