Preheat oven to 375 F. Lightly grease 12 muffin tin wells with non-stick cooking spray.
In a large mixing bowl, whisk together the 2 sugars, eggs, sour cream, vanilla and oil. Mix until smooth.
Add 2 cups of flour - 1/2 cup at a time - into the batter, then mix in the baking soda and salt.
In another small bowl, toss the blueberries and 1 Tbsp flour.
Melt the butter and toss with the crushed Vanilla Chex cereal.
Spoon the batter into the greased muffin tins and top with the "Vanilla Chex Streusel" and press lightly into the batter.
Bake in the preheated oven for 22 to 24 minutes.
Serve Blueberry Muffins with Vanilla Chex Streusel, warm with butter.