Use a lighter or kitchen torch to ignite one rosemary sprig. Once smoking, swiftly place it on a hollow dish and cover with cocktail glass. Allow the smoke to fill the glass for 20 seconds. Flip glass and discard rosemary sprig.
Add cardamom and vanilla sugar to a shallow dish or ramekin. Shuffle to combine. Coat rim of glass with 1 lime wedge. Dip wet rim in sugar, pressing down and twisting gently until rim is evenly coated.
Add peaches to glass. Muddle (gently mash) to release juices. Add 1 jumbo ice cube or ½ cup regular size ice cubes, peach bitters, peach shrubs, juice of two lime wedges, and tonic water. Stir to combine.
Ignite second rosemary sprig until smoking. Place in glass as garnish. Serve immediately.