Combine lemon juice, 1 tablespoon olive oil, scallions, and minced garlic in a large bowl.

Add whole and sliced squid, including tentacles to the marinade.

Cover and refrigerate the squid in the marinade for 4 hours.

Preheat oven to 400°F (200°C).

Combine 8 beets with 1 tablespoon olive oil in a baking dish.

Roast beets for 35-40 minutes, until tender.

Cool the roasted beets, peel them, and cut into 1/3-inch cubes.

Set aside the cubed roasted beets.

Dice the remaining 4 beets.

Combine diced beets and balsamic vinegar in a blender or food processor.

Puree until smooth.

Strain the beet puree into a bowl.

Whisk in the remaining olive oil to create a vinaigrette.

Season the vinaigrette to taste with salt and pepper.

Add the roasted beet cubes to the vinaigrette and toss to coat.

Set aside the beet salad.

Combine all onion confit ingredients in a large saucepan.

Simmer the onion confit over medium heat for 1 hour.

Set aside the onion confit to cool.

Increase oven temperature to 475°F (245°C).

Combine bread crumb ingredients in a large bowl.

Place whole squid sacs in a baking dish.

Place sliced squid and tentacles next to the whole sacs.

Pour the lemon marinade over the squid.

Top with the bread crumb mixture.

Bake the squid for 10-12 minutes, until tender.

Set aside the baked squid to cool slightly.

Spoon sliced squid and tentacles in the center of four plates.

Strain the beet salad, reserving the vinaigrette.

Ring the squid with a circle of minced beets.

Wreathe the beets with a circle of onion confit.

Arrange 3 whole squid sacs around the center.

Drizzle with the beet vinaigrette.

Garnish with chervil.

Serve immediately.