This recipe is a work of art and tastes great too!
In a small bowl, mix butter and sugar until fluffy. Beat in flour, vanilla, and cinnamon until smooth. Stir in nuts. Cover and chill at least 30 minutes.
Spray counter lightly with non-stick cooking spray. Roll dough into a 15x10 inch rectangle. Cover with plastic wrap and let rest while nut mixture is chilling.
Remove wrap from dough. Crumble filling evenly over the dough to within 1 inch of all edges. Start from long side of rectangle and roll dough tightly (as for a jelly roll).
With a sharp serrated knife, cut roll in half lengthwise. Carefully twist halves together so cut sides can be seen. Place on a sprayed baking sheet.
Cover with sprayed plastic wrap. Let rise until double. Remove wrap. Bake at 350°F 20-25 minutes. Cover with foil the last 5 minutes. While warm, drizzle with browned butter icing.
Browned Butter Icing:
Lightly brown butter in a small, heavy skillet over medium heat. Do not burn. Remove from heat and blend in powdered sugar. Blend in milk and vanilla until mixture is smooth.