If you make the caramel sauce ahead, reheat it in the microwave or a small saucepan over low heat until warm and fluid. When the hot cream mixture is added in step 3, the hot sugar syrup will bubble vigorously (and dangerously), so don’t use a smaller saucepan.

For a smooth pudding, it is important to pass the pudding through a fine-mesh strainer in order to remove any bits of cooked egg.

If the egg whites to be whipped are not at room temperature, set them in a pan placed in hot tap water and stir them until they are tepid. Coconut is very nice as a variation for this cake. Add 2/3 to 1 cup lightly packed sweetened flaked coconut, lightly chopped, to the batter before folding in the egg whites.

The longer you let the zest and juice mixture steep, the more intensely citrusy your margaritas will be. We recommend steeping for the full 24 hours, although the margaritas will still be great if the mixture is steeped for the minimum four hours. If you’re in a rush and need to serve the drinks immediately, omit the zest and skip the steeping process altogether. We suggest using reposado (“rested”) tequila, which is made from 100 percent blue agave and aged for between two and 12 months. Tasters liked its mellow flavor and thought it blended perfectly with the other ingredients.

The test kitchen prefers the hearty strands of egg-enriched fettuccine usually sold in 12-ounce boxes. We found that you need to salt the water used to cook the pasta and vegetables quite heavily to make sure they emerge nicely seasoned.

Refer to the illustrations below when layering the batter and streusel in the pan. A fixed-bottom, 10-inch tube pan (with 10-cup capacity) is best for this recipe. Note that the streusel is divided into two parts—one for the inner swirls, one for the topping.