Cut the two pieces of bread in half to give 4 portions. Arrange, cut side up, on a baking sheet and spread each piece with the onion chutney.
Lay the Brie slices on top and sprinkle with the thyme. Drizzle with the flavoured oil and cook under a preheated grill for 3–4 minutes, until the cheese begins to melt. Serve immediately with a tomato salad, if desired.