Instructions: 

1. Bring a pot of salted water to boil. Add ravioli and lower heat to a gentle boil, so as to avoid ravioli breaking open.
2. Heat hazelnuts in a small pan over medium-high, until fragrant and golden, making sure they don't burn. Set aside.
3. While water is heating, place a sauce pot over medium-high heat. Add champagne, champagne vinegar, and shallot. Split vanilla bean and, using the back of a paring knife, scrape out the seeds. Add the seeds and pod to the champagne mixture. Reduce the mixture until syrupy and about 1/4 c. Reduce heat to low.
4. Remove vanilla pod and add cold butter in batches, whisking vigorously until melted and incorporated. Add crème fraîche once all of the butter is used and add salt to taste.
5. Spoon warm sauce over lobster ravioli and garnish with a sprinkle of hazelnuts. Enjoy with a glass of bubbly!