Slice the tomatoes and chop the shallot. Wet the onion with a drizzle of olive oil, then add the tomatoes, sugar and thyme.
Covered, let it simmer for 15-20 minutes while stirring regularly. Season with salt, pepper and cayenne.
Mix the flour with the oil, add the egg yolk, a pinch of salt and water gradually. Beat the egg whites until stiff and add to the preparation.
Cut the Brie into pieces. Soak them in a little flour then in the batter and fry. Drain the oil out by placing them on absorbent paper.
Serve with the warm cherry tomato chutney.