Trim tops off beets, peel, halve, and cut into 1/2" dice. Halve Roma tomato lengthwise. Place red beets, golden beets, and tomato halves (cut side up) separately on one prepared baking sheet. Drizzle with 1 Tbsp. olive oil and toss beets and tomato halves separately. Roast 25-35 minutes, or until tomatoes are very soft and beets can be easily pierced with a knife.

While vegetables roast, drain capers. Halve baguettes lengthwise. Coarsely chop smoked almonds. Zest lemon, halve, and juice.

Place baguette halves on second prepared baking sheet and evenly distribute half the goat cheese (reserve remaining for garnishing tartines) on cut sides. Bake 4-6 minutes, or until cheese is slightly browned. Spread cheese on bread with knife--cheese will act as the "glue" to help keep toppings in place.

Once cool enough to handle, very finely mince roasted tomatoes. Add minced tomatoes and any accumulated juices to a medium mixing bowl. Add capers, 2 Tbsp. lemon juice, 2 Tbsp. olive oil, and 1/4 tsp. salt and whisk to combine.

Toss arugula with half the tomato-caper vinaigrette and serve salad on side. Place baguette halves on a plate and top each with remaining tomato-caper vinaigrette, 1/4 cup red beets, 1/4 cup golden beets, smoked almonds, and remaining goat cheese. Garnish with lemon zest. Any extra beets can be added directly to salad or saved for another use!