Adjust an oven rack to the center position and preheat the oven to 400 degrees. Have ready a 12-cup standard-size non-stick muffin pan and a can of cooking spray. Don’t spray the muffin cups just yet.
Combine the flour, baking powder, and salt in a food processor for 5 seconds. Empty the work bowl, reinsert the metal blade, and add the cranberries. Pulse 4 times to chop the cranberries medium-fine. Leave the cranberries in the work bowl until needed.
In a medium size bowl, use a hand-held electric mixer to cream the butter until smooth. Add the ¾ cup sugar and vanilla and beat well on medium speed for 3 to 4 minutes. Stop to scrape the bowl occasionally. This is the aeration step where you create the bubbles. Baking powder and heat will cause them to expand in the oven.
Add the egg and egg yolk.
Beat the egg and egg yolk in well, then beat in the orange zest.
Stir together the buttermilk and heavy cream in a 1-cup glass measure.
On lowest speed, mix in about one-third of the dry ingredients, then half the liquid, beating only until incorporated. Repeat with the remaining dry ingredients and liquid, ending with the dry. The batter will be thick.
Add the cranberries and pecans and fold them in.
Lightly coat each muffin cup with cooking spray.
Divide into muffin cups with an ice cream scoop or two soup spoons. Sprinkle top of each muffin with about ½ teaspoon sugar.
Bake muffins about 18 minutes, until lightly browned around the edges and they spring back when gently pressed in the center. Cool the muffins in the pan for 5 minutes, then carefully lift them out of their cups and arrange them in a napkin-lined basket.
Serve warm with butter.
To reheat, wrap loosely in foil and pop into a preheated 300 degree oven for about 5 minutes.