For the chili powder: Mix together the cumin, garlic powder, oregano, paprika, cayenne and salt.
For the bacon: Crisp the bacon in the olive oil in a saucepan over medium heat, about 10 minutes. Remove the bacon with a slotted spoon and set aside on paper towels. Keep the grease.
For the chowder: Brown the onions in the same saucepan, about 10 minutes. Sprinkle on the flour and chili powder. Cook for 1 minute. Add the chicken stock, corn and potatoes. Season with salt and pepper. Bring to a boil and simmer on medium-low until the potatoes are tender, about 20 minutes. Stir in the cream and remove from the heat.
Ladle the soup into bowls and garnish with cilantro and cheese. Sprinkle with the remaining chili powder and a squeeze of fresh lime juice. Serve with tortilla chips.