Have your son eat with the family on the same table. Seeing the adult picking up their veg, etc, might interest him to do the same. It works for mine at least. Currently 5 & loving vege & fruits.
I actually don't agree on blending all ingredients in a meal, especially so when the child is old enough to chew. If it's only for the purpose of getting the necessary nutrients, blending works fine. I prefer having the child to be aware of what they are putting into their mouth & getting to know the taste of individual food.