How to Make It

Step 1 Whisk together dry mustard, beer, 2 tbsp. water, and turmeric in a medium metal bowl until smooth. Chill, covered, overnight.

Step 2 Bring a medium saucepan filled with 1 inch water to a simmer. To bowl of mustard mixture, add egg, salt, cornstarch, lemon juice, and sugar and whisk to blend. Set bowl over saucepan and cook, whisking constantly, until the mustard just thickens, 4 to 6 minutes.

Step 3 Make ahead: 2 weeks, covered and chilled.

Step 4 Custom Mustard

Step 5 Your imagination's the limit when it comes to making flavored mustard. All you need are mustard seeds or dry mustard powder, and then the seasonings are up to you.

Step 6 Mustard seeds or mustard powder?

Step 7 Either works.

Step 8 Mustard seeds: Use when you want a whole-grain, crunchy texture. The three types are yellow, aka white (Sinapis alba), the mildest and used mainly in American-style mustards and for pickling; brown (Brassica juncea), zestier and used in European-style mustards (like Dijon), for pickling, and in Indian cooking; and black (B. nigra), also used in Indian food; they're interchangeable with the brown. Seeds need to soften in liquid for 1 to 2 days before you make mustard with them.