To make the crust mixture, pit and finely dice the olives. Whisk the butter until creamy, combine well with the diced olives and remaining ingredients, then refrigerate until the mixture starts to set.
To make the sauce, reduce the lamb stock to one-third its original volume, whisk in the butter to thicken, and season with salt and pepper.
Finishing: Brush the seared saddle of lamb with the crust mixture and roast in a 180°C for 8 minutes. Finish by broiling the crust under a salamander broiler.
Cook the Kenya beans in lightly salted water until tender, toss with butter and season with thyme leaves. Cut the potatoes into matchstick strips, wrap in bacon and fry in plenty of sunflower oil until golden brown.
Cut the saddle of lamb into several pieces and arrange on plates; garnish with the sauce and serve with the potato strips