Special equipment: a pastry bag; a small piping tip, such as the Ateco 0
Preheat the oven to 200 degrees F. Set a baking rack on a baking sheet and put it in the oven.
For the glaze: Put the cream cheese in a bowl. Heat the maple syrup in a small saucepan over low heat until it just begins to simmer, then pour over the cream cheese and whisk vigorously until smooth. Set aside and keep warm.
For the cinnamon swirl: Melt the butter in a small saucepan until light golden brown. Whisk in the muscovado sugar and cinnamon; the sugar may clump and separate from the butter¿don't worry. Whisk in 1/4 cup water and bring to a simmer, whisking until the mixture smoothes out. Simmer until slightly thickened, about 2 minutes. Whisk in the cream and simmer another 2 minutes. Transfer to a small bowl to cool--the mixture will thicken as it cools--then transfer to a piping bag with a small tip.
For the pancakes: Whisk together the flour, sugar, baking powder, baking soda and salt in a large bowl. In a medium bowl, whisk together the buttermilk, 3 tablespoons melted butter, eggs and vanilla. Add the wet mixture to the dry and whisk until just combined.
Heat a large nonstick pan or cast-iron griddle over medium heat and brush with some melted butter. Ladle about 1/4 cup of the batter into the pan and spread to make a 4-inch circle. Ladle in a few more pancakes, being careful not to crowd them.
When the pancakes just begin to form bubbles on the surface, pipe in the cinnamon swirl filling: Starting at the center of the pancakes, squeeze the filling on top in a swirl (just as you see in a regular cinnamon bun). Continue cooking until larger bubbles begin to appear, the surfaces are somewhat dry and set, and the bottoms are light golden brown, about 2 minutes--adjust the heat as necessary so the bottoms don't brown before the tops set. Flip over and continue cooking until golden brown on the reverse side, about 1 minute longer.
Transfer the pancakes to the oven to keep warm while you make the rest of the pancakes.
To serve: Stack 3 pancakes on each plate, drizzle with some of the maple cream cheese glaze, and sprinkle with pecans.