Air Fryer Berry Crisp

FRUIT FILLING

• 1 c. fresh raspberries
• 3/4 c. fresh blueberries
• 1/2 c. fresh blackberries
• 2 tbsp. granulated sugar
• 2 tsp. ground flaxseeds
• 1/2 tsp. pure vanilla extract
• Pinch of kosher salt

TOPPING

• 1/3 c. whole wheat flour
• 3 tbsp. old-fashioned rolled oats or chopped nuts, such as almonds or pecans
• 1 tbsp. granulated sugar
• Pinch of kosher salt
• 2 tbsp. butter softened
• Olive oil cooking spray