Here's a recipe for classic chocolate brownies that serves 12 and includes information on ingredients, calories, fat, preparation, and total time:

Ingredients:

• 1/2 cup (1 stick) unsalted butter, melted
• 1 cup granulated sugar
• 2 large eggs
• 1 teaspoon vanilla extract
• 1/2 cup all-purpose flour
• 1/2 cup unsweetened cocoa powder
• 1/4 teaspoon salt
• 1/4 teaspoon baking powder

Calories and Fat:

• The entire recipe contains approximately 1816 calories and 90 grams of fat.
• Each serving (assuming 12 servings total) contains approximately 151 calories and 8 grams of fat.

Preparation:

• Preheat the oven to 350°F (175°C) and grease an 8-inch (20cm) square baking pan.
• In a medium mixing bowl, stir together the melted butter and granulated sugar until well combined.
• Add the eggs and vanilla extract to the mixture and whisk until smooth.
• In a separate mixing bowl, whisk together the flour, cocoa powder, salt, and baking powder.
• Add the dry mixture to the wet mixture and stir until just combined.
• Pour the brownie batter into the greased baking pan and smooth out the top with a spatula.
• Bake the brownies in the preheated oven for 20-25 minutes, or until a toothpick inserted into the center comes out mostly clean.
• Remove the brownies from the oven and let them cool in the pan for 10-15 minutes before slicing and serving.

Total time: Approximately 40-50 minutes, including preparation and baking time.