Blackberry Cobbler

I was zooming through the produce section at Costco a couple weekends ago when I spotted a great deal on about 4 cups worth of blackberries. Of course, the first thing that popped into my head was cobbler!
Typically I take a couple cobbler recipes that I've collected over the years and 'borrow' techniques from each of them to create a yummy cobbler. This time I decided to find a new recipe and I think I've found a winner!

The recipe is here on Allrecipes.com and I adapted it just a little bit.

Ingredients:

• 1 cup all-purpose flour
  
• 1 1/2 cups white sugar, divided
  
• 1 teaspoon baking powder
  
• 1/2 teaspoon salt
  
• 6 tablespoons cold butter
  
• Cinnamon
  
• 1/8 tsp vanilla
  
• 1/4 cup boiling water
  
• 2 tablespoons cornstarch
  
• 1/4 cup cold water
  
• 1 tablespoon lemon juice
  
• 4 cups fresh blackberries, rinsed and drained
  

Directions:

1. Preheat oven to 400 degrees F (200 degrees C). Line a baking sheet with aluminum foil.
   
2. In a large bowl, mix flour, 1/2 cup sugar, baking powder, salt, and a couple dashes of cinnamon. Cut in butter until the mixture resembles coarse crumbs. Add vanilla, then stir in 1/4 cup boiling water just until mixture is evenly moist.
   
3. In a small cup, dissolve the cornstarch in cold water. Add blackberries, 1 cup sugar, lemon juice and the dissolved cornstarch/water mix to cast iron skillet and stir to incorporate. Bring the skillet to a boil, stirring frequently and cook just a couple minutes. Drop dough into the skillet by spoonfuls. Place skillet on the foil lined baking sheet.
   
4. Bake 25 minutes in the preheated oven, until dough is golden brown.