Bring a pot of salted water to a boil. Blanch the asparagus for 1 minute, then shock in a bowl of ice water.

Heat a pan over medium-low heat. Add a drizzle of olive oil and the cherry tomatoes with a pinch of salt. Cook 7–10 minutes until softened and blistered, then remove from heat.

Increase heat to medium, add asparagus with another pinch of salt, and cook 4–5 minutes until browned. Remove from heat.

In a bowl, stir together dijon mustard, white wine vinegar, and olive oil. Add capers, cornichons, hard-boiled egg, and season with salt, pepper, and vinegar to taste. Mix in parsley just before serving.

To serve, plate asparagus and cherry tomatoes, drizzle generously with sauce gribiche, and finish with crushed hazelnuts and flaky salt.