In a small bowl, combine warm milk, yeast, and a pinch of sugar. Let sit about 5 minutes to proof until foamy.

In a large bowl, whisk together flour, remaining sugar, and salt. Add melted butter, egg, and yeast mixture; stir until a shaggy dough forms.

Turn dough onto a lightly floured surface; knead 5–7 minutes until smooth and elastic, adding flour if too sticky. Form into a ball.

Place dough in a greased bowl, cover, and let rise in a warm spot until doubled in size (~1 hour).

Punch down the dough and roll into a 12×16‑inch rectangle on a floured surface.

Spread the softened butter evenly over the dough. In a separate bowl, mix brown sugar and cinnamon, then sprinkle evenly over the buttered dough. Finally, sprinkle chopped Snickers pieces across the filling layer.

Starting from a long side, tightly roll the dough into a log. Pinch seam to seal. Cut into 9–12 equal rolls using floss or a sharp knife.

Place rolls in a greased 9×13‑inch baking pan; cover and let rise again until nearly doubled, about 30–45 minutes.

Preheat oven to 350 °F (175 °C). Bake the rolls for 20–25 minutes, or until golden‑brown and cooked through.

Meanwhile, whisk together powdered sugar, milk (or cream), and vanilla until smooth and drizzleable.

Remove rolls from oven; let rest 5 minutes, then drizzle glaze generously over warm rolls. Serve warm.