In a large bowl, mix the garlic powder with 1 1/2 teaspoons salt and 1/4 teaspoon cracked black pepper. Pat the beef dry with paper towels and add to the bowl; toss to coat. Add 1/3 cup of the flour and toss again.
In a Dutch oven, heat the oil over medium-high. Working in batches, add the beef and cook until browned on all sides, about 5 minutes per batch. Transfer to a plate. Reduce the heat to medium and add onion. Cook, stirring often, until fragrant and starting to soften, about 2 minutes. Add the cognac and cook, scraping up any brown bits with a spoon, about 1 minute. Return the meat to the pot and add the beef broth. Bring to a simmer, reduce heat to low, cover and simmer, stirring occasionally, until the beef is almost tender, about 1 1/2 hours.