Gin Old-Fashioned

Soak sugar cube with bitters in mixing glass. Gently muddle to combine. Add gin and ice, and stir until chilled. Strain over Peychaud's bitters ice sphere* into tumbler.   *Add 6 dashes Peychaud's bitters to water in sphere ice mold then freeze.
CREDIT: Daphne Dee (recipe) + Cocktails by Folly (photography)