-
1
Line 15x10-inch rimmed baking sheet with foil.
-
2
Combine 4 cups water and 1 teaspoon salt in heavy large saucepan.
-
3
Bring to boil.
-
4
Gradually add polenta, whisking until smooth.
-
5
Reduce heat to medium-low; cook until polenta thickens and pulls away from sides of pan, whisking frequently, about 30 minutes for polenta and 15 minutes for yellow cornmeal.
-
6
Whisk in butter and 1 teaspoon oregano.
-
7
Pour out polenta onto prepared baking sheet; spread evenly to edges of sheet.
-
8
Chill until firm, at least 2 hours or overnight.
-
9
Preheat oven to 300F.
-
10
Line another large baking sheet with parchment paper.
-
11
Arrange tomato slices in single layer on prepared sheet.
-
12
Sprinkle tomatoes with 1/2 teaspoon sugar, then some salt.
-
13
Drizzle with 2 tablespoons oil.
-
14
Roast until tomatoes are tender but sides are firm and slices still hold together, about 2 hours.
-
15
Cool.
-
16
(Polenta and tomatoes can be made 1 day ahead.
-
17
Cover separately and chill.)
-
18
Preheat oven to 450F.
-
19
Line another large baking sheet with parchment paper.
-
20
Using 1 3/4- to 2-inch-diameter cookie cutter, cut out 24 rounds from polenta.
-
21
Place rounds in single layer on prepared sheet.
-
22
Top each round with 1 tomato slice.
-
23
Sprinkle with remaining 1 teaspoon oregano.
-
24
Top each with 2 or 3 olive halves.
-
25
Drizzle with remaining 2 tablespoons oil, then sprinkle with Parmesan.
-
26
Bake polenta pizzas until heated through and cheese melts, about 10 minutes.
-
27
Serve warm.
