• If you're using a baking stone or steel, place it on a rack in the bottom third of your oven. Preheat the oven to 400°F.

To make the beet sauce

• Divide the beets among 2 rectangles of aluminum foil. Drizzle with olive oil, and sprinkle each mound of cubed beets with ¼ teaspoon salt. Fold up the foil into sealed packets and roast for 35 to 45 minutes, until the beets are fork tender.
• Dump the roasted beets into the bowl of a food processor and add the 1 tablespoon of olive oil, ½ teaspoon of salt, mint, and lemon juice. Process until the beets are broken down and the mixture resembles a smooth sauce. Taste and add more salt and/or lemon juice as desired.
• Increase the oven temperature to 500°F or as high as your oven will go.

To form the dough into a heart shape (optional)

• Put the ball of dough on a floured work surface, flatten it to a 6-inch round, and then roll it out in a V shape. The dough will shrink back a bit, so you may need to stretch it gently to make the shape look heart-like. If it keeps shrinking, let it sit for 15 minutes, covered with a piece of plastic wrap or a clean kitchen towel, and then try again. Pinch or or press together the bottom of the heart to make a clear V, then keep shaping the dough until the widest part of your heart shape is about 12 to 14 inches across. Prick the dough all over with a fork to prevent large bubbles from forming in the oven.

To top the dough

• If you’re using a baking stone or steel, switch the oven to Broil on high.
• Brush off any excess flour from the bottom of your pizza dough heart, and transfer the dough to an oiled baking sheet or lightly floured pizza peel (if using a baking stone or steel).
• Spread the beet sauce on top of the dough, leaving a ½-inch border all around. (You might have extra beet sauce, depending on the size of your pizza dough heart; see notes for other uses.) Sprinkle on the almonds and goat cheese.
• Transfer the pizza to the oven and bake until the crust is golden and the cheese has browned in spots—8 to 10 minutes on the baking sheet, 6 to 8 minutes on the baking stone/steel.
• Remove the pizza from the oven and let it rest for a few minutes, then scatter on the arugula and drizzle with the balsamic glaze. Slice and serve.