Rajas con Crema

4 large poblano peppers

2 tablespoons butter

1 onion, sliced

2 large cloves garlic, minced

3/4 cup Mexican crema

1 teaspoon salt, or to taste

1 teaspoon chicken bouillon granules, such as Knorr®

1/4 teaspoon freshly ground black pepper

1 cup shredded Oaxaca cheese