In a mixing bowl, combine Bisquick and sugar. Mix these dry ingredients well.
Add milk and combine. Set aside.
Grease a 6 quart slow cooker with nonstick cooking spray and pour canned peaches (with syrup) into the bottom of the slow cooker.
Gently pour Bisquick mixture on top, which will mix in with the peaches and syrup. Do not stir.
Place a layer of paper towel on top of the slow cooker and place the lid on the slow cooker. This helps catch condensation that may appear on the lid. If the paper towel gets full during cooking, replace with a fresh paper towel.
Cook Peach Cobbler on high in slow cooker for 2 to 2.5 hours, until Bisquick is cooked through.
Serve warm with vanilla ice cream and top with crunchy pecans.