Demerara Dry Float
Shake everything except the 151, strain into a double old fashioned over crushed ice, float 151.
The best way to make passionfruit syrup is to take frozen passionfruit pulp, thaw it, and mix that with an equal amount of 1:1 simple syrup.
- My spec: 1 oz Lemon Hart 151, 0.5 oz Smith & Cross, 0.25 oz other aged rum (Kirkland 12 year), 1 oz passionfruit syrup (Liber & Co), 1.25 oz lime juice, 0.25 oz velvet falernum, 0.25 oz Luxardo maraschino. Garnish: oil expressed from a lime peel. 4 stars
It almost seems to me that the 151 and regular Demerara rum amounts should be reversed. I'd use the best Demerara rum you can find, as it's got to stand up to a huge amount of lime juice.
Because this recipe wasn't strange and scary enough as is, I'm going to try it with the full ounce of 151.