Cook the baby potatoes in their skins, your own way. Preheat the oven to 230°C. Grease the bottom of a large baking dish with oil and sprinkle with pepper and salt. Check the salmon fillet for bones. Place it in the baking dish and brush it with olive oil.
Break off the tough end of the asparagus and brush them on all sides with 1 tablespoon of olive oil.
Gently crush the cooked baby potatoes with a large knife and cut the lemon into 8. Mix the potatoes, lemon wedges, olives, capers, 2 tablespoons of olive oil, and pepper. Arrange them around the salmon, place the asparagus on top, sprinkle with 4 sprigs of thyme, and bake in the oven for 15 minutes.
Meanwhile, make the sauce: mix the honey and mustard. Gradually add the olive oil while whisking the sauce, just like making mayonnaise. Add 1 tablespoon of grated orange zest and the juice of half an orange.
Sprinkle the salmon with fresh thyme and serve the sauce on the side.