Pastry Cream

Heat half-and-half, 3/4 of the sugar, and salt in medium heavy-bottomed saucepan over medium heat until simmering, stirring occasionally to dissolve sugar.

Meanwhile, whisk egg yolks in medium bowl until thoroughly combined. Whisk in remaining sugar and whisk until sugar has begun to dissolve and mixture is creamy, about 15 seconds. Whisk in cornstarch until combined and mixture is pale yellow and thick, about 30 seconds.

When half-and-half mixture reaches full simmer, gradually whisk simmering half-and-half into yolk mixture to temper. Return mixture to saucepan, scraping bowl with rubber spatula; return to simmer over medium heat, whisking constantly, until 3 or 4 bubbles burst on surface and mixture is thickened and glossy, about 30 seconds. Off heat, whisk in butter and vanilla. Transfer mixture to medium bowl, press plastic wrap directly on surface, and refrigerate until cold and set, at least 3 hours or up to 48 hours.