Mince the garlic and parsley; set aside separately.
Rinse shrimp; pat shrimp dry; set aside.
Heat a large frying pan. Add butter and oil.
Zap a heat-proof bowl in the microwave to warm it somewhat; set aside
When the oil and butter is hot (don't let the butter brown) , add the shrimp, let cook without stirring for 1 minute. Add the garlic, again without stirring, and let cook for another minute. Then stir to turn the shrimp over, and let cook for 2 minutes.
Transfer the shrimp to the warmed bowl and cover. Put the frying pan back on the heat, let heat up for a minute, then add the vermouth and lemon juice and cook for 30 seconds to make a sauce. Scrape the pan to deglaze the flavour bits into the sauce, then stir in the zest and parsley.
Pour all this sauce over the shrimp in a bowl, and season as desired with salt and pepper (freshly ground if you have it, otherwise don't sweat it.)
Send to the table.
Use large shrimp (aka "prawns").Best done in a frying pan which isn't non-stick.