Prepare all ingredients as listed.
In a small bowl, mix the butter, chives, parsley, Dijon mustard, and grated garlic until well combined, then season with salt and black pepper to taste.
In a separate bowl, toss the arugula with the lemon juice and season lightly with salt and black pepper.
Slice the rolls and spread the herb butter mixture evenly on the inside of each roll.
Layer the deli ham, Brie cheese, and dressed arugula inside the rolls to assemble the jambon beurre sandwiches.
In a pitcher or large glass, combine the sparkling water, lemon slices, and chia seeds, stirring well, then let sit for 2–3 minutes and stir again to prevent clumping.
Serve the sandwiches with carrot sticks, hummus, sliced pear, and the lemon chia sparkling water.