2–3 tablespoons unsalted butter, for grilling/toasting
2 tablespoons hot English mustard (or alternatively, dijon), for serving
10–15 cornichons, for serving
Instructions
In a large pan over low-medium heat, add 2 tablespoons of the butter. Once the butter has melted, add the onion, garlic, and dates and cook slowly (without scorching, and while stirring every now and then), until onions and garlic are fragrant, translucent, and slightly golden in color (about 10 minutes). Add chicken stock, increase heat to medium-high, and use a spatula to scrape up any bits from the bottom of the pan. Cook for another 5-7 minutes, until the liquid has thickened but not fully reduced (it should be about as thick as heavy cream).
Remove from heat and allow a few minutes to slightly cool, then transfer to a blender or food processor with the remaining 6 tablespoons of butter, walnuts, balsamic vinegar, and salt. Blend until smooth, taste, and make any necessary adjustments (add more salt or vinegar, to taste). Transfer to small serving bowls or ramekins and set aside. (Note: the date pâté can also be prepared ahead and stored in the fridge in an airtight container for up to one week.)
Prepare your accompaniments: Add butter to a hot skillet and grill/toast baguette slices until golden brown on both sides and transfer to a serving plate. Transfer hot English mustard and cornichons to small serving bowls. Remind your guests to get a little bit of everything in every bite.