Set oven to 350 degrees F. Mix together milk and lemon juice to create buttermilk. Stir and set aside for 10 minutes to thicken.. In a medium size bowl, whisk together egg and sugar.
Whisk in vanilla extract, buttermilk and half & half. Whisk in soft butter. In a small bowl, sift together flour, baking powder, cinnamon, nutmeg, and salt.
Whisk flour mixture into batter until smooth. Grease muffin pan or use muffin papers. Bake 18-20 minutes and then check for doneness by touching gently in the center. If they bounce back take them out and set on cooling rack.
In a small bowl, mix together sugar and cinnamon for topping. Melt butter in the microwave in a bowl. Dip muffins upside down into butter and then dip into cinnamon sugar mixture. Set on wire rack.