Prepare ingredients: Prepare all ingredients as listed. Remove the Brie from the refrigerator and let sit at room temperature for about 5 minutes so it softens slightly.
Make herb butter: In a small bowl, mix the softened butter, chives, parsley, Dijon mustard, and grated garlic until well combined. Season with salt and black pepper to taste.
Dress the arugula: In a separate bowl, toss the arugula with lemon juice and a light pinch of salt and black pepper. Set aside.
Assemble sandwich: Spread the herb butter inside the rolls. Layer with deli ham, Brie, and arugula. Cut in half if preferred.
Make mango lassi: In a blender, combine the ingredients. Blend until completely smooth and creamy. Taste and adjust sweetness if needed.
Serve the jambon beurre with carrot sticks, hummus, pickle spears, and mango lassi.