Bring all ingredients to a boil and let simmer until mustard seeds are soft (about 10 min), strain off remaining liquid and let cool. Store in refrigerator until needed
Plating suggestion: Use a long, rectangle type plate. Place the pork on the left-hand side with a streak of the hazelnut cream along the center, trailing off to the right. Fan the roasted apple on the right-hand side and sprinkle with the roasted hazelnut. Dollop the mustard caviar directly on the pork and add a sprig of mint to garnish.