Preheat the oven to 375°F (190°C).

Toss beets with 1 tablespoon olive oil, salt, and pepper.

Place beets in a baking dish and add 1/2 cup water to cover the bottom.

Cover with foil and bake for 1 hour, or until tender.

Add more water if it evaporates.

Cool slightly, peel beets, and cut into 8 wedges.

Return beets to the baking dish; leave the oven on.

Finely grind pistachios in a mini processor and spread on a plate.

Blend Roquefort cheese with heavy cream in a bowl.

Spoon 1/2 teaspoon cheese mixture into each date half.

Roll dates in pistachios to coat.

Melt butter in a large skillet.

Add sugar and 1/2 tablespoon lemon juice; cook over medium heat until sugar caramelizes (about 3 minutes).

Add endives, stir to coat, and cook until softened (about 5 minutes).

Raise heat to medium-high and cook until liquid evaporates and endives are caramelized (about 7 minutes).

Add remaining 1 tablespoon lemon juice, salt, and pepper.

Remove from heat.

Combine sherry vinegar, canola oil, walnut oil, and remaining 1 tablespoon olive oil in a small bowl; season with salt and pepper.

Rewarm beets in the oven for 4 minutes.

Toss beets with 1/4 cup dressing; add chives, salt, and pepper.

Rewarm endives in the skillet.

Toss watercress with remaining 2 tablespoons dressing.

Arrange 8 beet wedges on each salad plate.

Spoon caramelized endives onto plates; top with 3 stuffed dates per serving.

Garnish with watercress and serve.