Sort through wheat berries carefully; discard any stones. Rinse well. Place in a large heavy saucepan and add water to cover by 2 inches. Bring to a boil, reduce heat to medium-low, cover and simmer, adding more water if necessary, until the wheat berries are tender, about 1 hour. Drain well.

Place the wheat berries and 2 tablespoons milk in a food processor. Pulse, scraping down the sides as necessary, until most of the wheat berries are coarsely chopped (some may remain whole).

Combine the chopped wheat berries, the remaining 3 cups milk, cinnamon stick, orange zest and salt in a Dutch oven or other large, heavy-bottomed pot and bring to a boil. Reduce heat to medium-low and cook, stirring often to prevent sticking, until the mixture is very thick, 25 to 30 minutes. Remove from the heat; discard the cinnamon stick and orange zest. Stir in maple syrup and vanilla.

Serve warm or chilled, sprinkled with cinnamon and topped with a dollop of maple yogurt, if desired. (Stir in more milk if the pudding gets too thick as it stands.)

Note: Wheat berries of any variety (hard, soft, spring or winter) can be used interchangeably. Labeling is inconsistent - you may find them labeled "hard red winter wheat" without the words "wheat berries." Find them in natural-foods markets and online at kingarthurflour.com. Some recipes instruct soaking overnight, but we found it unnecessary.

To cook: Sort through wheat berries carefully, discarding any stones, and rinse with water. Bring 4 cups water or broth and 1 cup wheat berries to a boil. Reduce heat to a simmer, cover and cook, stirring occasionally, until tender, but still a little chewy, about 1 hour. Drain.

MAKE AHEAD TIP: Cover and refrigerate the cooked wheat berries (Step 1) for up to 2 days or freeze for up to 1 month. Cover and refrigerate the pudding for up to 2 days.