In a large mixing bowl, cream together the butter and sugar until light and fluffy, about 3-5 minutes. Beat in the eggs and vanilla extract until well combined. In a separate bowl, whisk together the flour, baking powder, baking soda, and salt, then gradually add this dry mixture to the wet ingredients. Chill the dough in the refrigerator for 30 minutes to firm up.

While the dough chills, prepare the creamy filling. In a clean mixing bowl, whip the heavy cream with powdered sugar and vanilla extract until stiff peaks form, about 3-4 minutes. Set aside in the fridge to keep cool.

Preheat your oven to 350°F (175°C) and line baking sheets with parchment paper. Scoop rounded tablespoons of chilled dough onto the prepared sheets, leaving space in between. Bake for 10-12 minutes, or until the edges are lightly golden. Cool the cookies on the sheets for about 5 minutes before transferring to a wire rack.

In a small microwave-safe bowl, combine the chocolate chips and vegetable oil. Microwave in 30-second intervals, stirring until smooth and fully melted, about 1-2 minutes total. Allow the glaze to cool slightly.

Once the cookies are completely cooled, take one cookie and pipe or spread a generous dollop of cream filling on the flat side. Place another cookie on top to create a sandwich. Dip the top of each assembled cookie into the chocolate glaze, letting any excess drip off. Place on a wire rack to set the glaze.