Brown Sugar Plum Cobbler - Serving Dumplings

Ingredients

• 2 pounds plums (pitted and quartered)
• ¾ cup brown sugar
• 2 tbsp rum (optional)
• 1 tsp vanilla
• 1 tsp cinnamon
• 1 tbsp lemon juice
• 1 tbsp corn starch
• butter for greasing
• coarse sugar for sprinkling
• vanilla ice cream (for serving)
• powdered sugar (for serving)
• 1 cup all-purpose flour
• 3 tbsp sugar
• 1 ½ tsp baking powder
• ¼ tsp salt
• ½ cup whole milk (at room temperature)
• 3 tbsp unsalted butter (melted)