For the curry paste, fry coriander and mustard seeds in a frying pan without fat. Take out. Peel ginger, garlic, shallots and galangal and finely dice everything together.
Remove outer leaves from lemongrass. Chop the inside finely. Clean chilies, score lengthwise, remove seeds, rinse and chop.
Cut 3 roots of coriander into small pieces, rinse and chop.
Rinse lime and cilantro leaves, rub dry and chop.
Finely pound prepared ingredients in a mortar or coarsely grind in a hand blender. Mix in shrimp paste and oil. Rinse the duck breast fillets, rub dry and score the skin. Sear in a frying pan without fat, first on the skin side for about 5 min, then on the meat side for 2-3 min. Roast over medium heat, turning, for another 10-15 min.
Clean, rinse and drain spinach. Dice tofu. Season duck breast fillets with salt and remove. Wrap in aluminum foil and rest. Pour out all but 2 tbsp of the drippings from the frying pan. Roast tofu in frying pan for 5 min until crispy. Season with salt. After 3 min, add sesame seeds and peanuts to roast.
Add spinach, drop together. Mix in curry paste and continue cooking at low temperature for about 5 min. Cut duck breast fillets into slices, arrange on curry. Serve with basmati rice.
Tip: Did you know that one bowl of spinach provides almost all the manganese and fiber you need?