Dot the butter evenly across the blackberry layer before adding the cake mix topping to ensure crispy, golden spots throughout rather than pooling in one area.

Use frozen blackberries straight from the freezer without thawing—they release juice more slowly during baking, preventing a soggy bottom layer and creating a better texture contrast.

Mix cinnamon and sugar together before sprinkling over the cake mix layer to distribute the spice evenly and prevent clumping for a more uniform, flavorful topping.

Squeeze fresh lemon juice over the blackberries before topping to brighten the berry flavor and balance sweetness, which complements the cake mix perfectly.

Let the cake cool for 10-15 minutes after baking before serving—this allows the berry juices to set slightly so scoops hold together while still remaining warm for ice cream melting.