Melt block of butter and cool

Preheat oven to 350°

Lightly grease a 13x9 pan

Combine all dry ingredients in a large mixing bowl

Combine milk, eggs and vanilla extract in a separate bowl

Add melted butter to wet ingredients (if still warm, slowly add butter while mixing)

Pour wet ingredients into dry ingredients and mix well until there are no lumps

Pour batter into 13x9 pan and bake for 1 hour