The tomatoes should first be washed and then briefly blanched to peel off the peel. Then cut into large cubes. Peel the ginger and cut into as fine cubes as possible. Cut the shallots into medium-sized cubes.
Put all ingredients except the mustard seeds in a saucepan and bring to a boil. Simmer for about half an hour until the onion cubes have a soft consistency.
Then roast the mustard seeds with the oil in a pan so that they develop the taste better (be careful, they like to jump out of the pan) and add.
When the chutney begins to thicken (after 10-15 minutes), pour it hot into freshly rinsed jam jars or wake it up.