Preheat the oven to 350 degrees F.
In a medium bowl, mix together the spinach and cream cheese.
Add garlic, salt, onion powder, chili powder and stir to combine.
Add parmesan cheese and half of the mozzarella cheese and mix to combine. The other half of the mozzarella cheese will be sprinkled over the filling when you shape the Christmas tree.
Open the can of pizza crust dough and spread it out flat. Use a pizza cutter to cut a large triangle from the center of the dough.
Reserve the remaining dough triangles to go over top of the spinach filling.
Place the large triangle of pizza dough on a parchment paper lined baking sheet.
Spread the spinach dip mixture over the dough, leaving the edges uncovered. Top with remaining cheese.
Place the second dough triangle over the spinach covered layer. Press the edges together.
Use a sharp knife or pizza cutter to cut slits into each side of the dough tree about two inches into the tree and one inch apart. Twist each of these pieces a few times to create breadsticks.
Melt the butter and stir in garlic salt, then brush over the entire tree.
Bake for 25-30 minutes until quite golden brown on top and cooked through on the bottom.
Serve warm. Guests can pull each breadstick from the tree as they would like.