1. Place the diced butter in the bowl of the robot equipped with the beater attachment.
2. Add the lemon juice, egg yolks, and 4 tablespoons of water.
3. Season with salt and pepper.
4. Cook for 8 minutes in sauce mode at speed 6 at 70°C. Set aside.
5. Cook rice in a rice cooker.
6. Place the salmon on 4 squares of parchment paper.
7. Arrange the peeled asparagus with trimmed ends on top of the salmon.
8. Season with salt and pepper.
9. Seal the papillotes tightly. Pour 70 cl of water into the bowl and place the papillotes in the steam basket.
10. Cook for 15 minutes with the steam program P1.