Add apple and pear slices to a 32 oz mason jar, then add enough gin to cover the fruit, about 10 oz. Note that you'll only need 2 oz of infused gin per serving.
Allow the gin to rest for 7 days in a cool, dark spot. Strain fruit from the gin and return to a clean mason jar for storing any that you don't drink right away.
Add ice to 2 lowball glasses, then divide ingredients evenly between the glasses. Garnish with dried apple, cinnamon stick, and fresh herbs like rosemary or thyme.