Preheat your oven to 350°F (175°C) and line baking sheets with parchment paper.

In a large mixing bowl, combine softened butter, vegetable oil, and brown sugar. Beat until fluffy, about 2-3 minutes. Add in the egg and vanilla, mixing until incorporated. Gradually sift in the flour, baking soda, baking powder, salt, and cinnamon, stirring gently until just combined.

In a separate bowl, mix softened butter, brown sugar, flour, cinnamon, and a pinch of salt for the streusel topping until it resembles coarse crumbs.

Shape the dough into uniform balls, placing them on the lined baking sheet. Create a deep indent in the center of each ball.

Bake for approximately 10-12 minutes, or until golden brown. Allow cooling on the sheet for a few minutes.

In a small bowl, mix powdered sugar, milk, and vanilla until smooth for the icing drizzle.

Drizzle the icing over each cookie and serve warm with your favorite coffee or tea.