Preheat the oven to 240°C. Dice the bacon rashers, discarding the rind. Heat the oil and fry the bacon pieces until crisp then drain on paper towels.
To make the dressing, peel the garlic, crush it into a small bowl, then whisk in the mustard, vinegar and olive oil. Season to taste with salt and pepper.
Line a baking tray with baking paper. Cut the goat's cheeses in half horizontally to get four slices and place on the paper. Bake for 5 minutes or until the cheese begins to melt and turns a toasty brown on top.
Meanwhile, trim, rinse and dry the rocket or watercress and put into a mixing bowl with the bacon. Pour over the dressing and toss lightly, then arrange in circles on individual plates.
Remove the cheese from the oven, place one round in the centre of each salad and serve immediately.
For a vegetarian version, use lightly toasted pine nuts or almonds instead of the bacon.