To make the cake, mix salad oil, cream cheese, egg and half and half in a bowl. Mix well.
In another bowl, sift together flour, sugar, baking powder and salt. Add to wet ingredients and mix well.
To make topping, mix brown sugar, flour, cinnamon, nutmeg, pecans, and melted butter in a bowl.
Pour cake batter into a greased 9 x 9 inch pan. spread blueberries evenly over batter. Sprinkle evenly with topping. Bake for 30 to 35 minutes or til toothpick inserted in center comes out clean. Makes 8 servings.