Preheat oven to 350°F. Line 2 baking sheets with parchment paper or a silicone baking mat.
To make cookie dough: Using an electric mixer, cream together butter, brown sugar and vanilla beating at high speed for about 3-5 minutes or until fluffy and light beige in color. Add egg, beat well.
In a separated bowl, use a whisk to sift together flour, baking powder and salt. With mixer on low speed gradually add dry ingredients to creamed mixture beating just until fully combined.
Cover and chill dough for 30-45 minutes. Use a small scoop or a Tbsp to divide the dough. Shape dough into approximately 1 ½ inch balls, placing at least 2 inches apart on prepared pans. (Make sure there are no cracks and dough is smooth)
To make the filling: In a small bowl, mix together pecans, brown sugar, cream and vanilla.
To fill: Use your thumb to make an indentation in the center of each dough ball, rotating to hollow out slightly. Fill with 1 rounded tsp of filling. (You can also use a teaspoon or the back of a small scoop to hollow)
Bake for 10-12 minutes or just until lightly golden. Cool on pan for 2-3 minutes. Remove to a cooling rack to cool completely.
Store leftovers in an airtight container at room temperature for up to 3 days.