Prepare the Cherries: Drain the maraschino cherries and mince them finely. Place between paper towels to remove excess moisture.

Cream the Butter and Sugars: Beat the softened butter, vegetable oil, granulated sugar, and powdered sugar until light and fluffy.

Incorporate the Wet Ingredients: Add the eggs, almond extract, cherry extract, and prepared cherries. Mix until combined.

Combine the Dry Ingredients: Whisk together flour, baking soda, and cream of tartar. Fold into the wet mixture until just combined.

Preheat the Oven: Preheat to 375°F (190°C) and line baking sheets with parchment paper.

Shape the Cookies: Drop spoonfuls of dough onto the prepared sheets, spacing them 2 inches apart.

Bake to Perfection: Bake for 8-11 minutes until lightly browned around the edges. Cool on racks.

Prepare the Icing: Whisk melted butter, cherry juice, almond extract, and powdered sugar until smooth.

Frost and Garnish: Frost cooled cookies with icing and sprinkle slivered almonds on top.