Preheat a skillet over medium heat. Add ground beef and season with salt, pepper, granulated garlic, and cumin. Cook, breaking up the beef, until browned.
Push the beef to one side of the skillet and add onions, garlic, and poblano pepper to the other side. Sauté for 3-4 minutes, then mix into the beef.
Stir in one diced tomato, cooking for an additional 3 minutes until softened.
In a blender, combine the remaining tomato, serrano pepper, bouillon, and ½ cup of water, blending until smooth. Pour this mixture into the skillet and bring to a boil, adjusting salt and pepper as needed.
Add the whole serrano pepper, corn, zucchini, and oregano. Stir well, reduce heat slightly, and simmer for 10-15 minutes, stirring occasionally.
Remove from heat, let rest for 10 minutes, and serve on tostadas or with warm tortillas.
Enjoy!