Frozen Watermelon-Lime Bars

Line a 9-inch square baking pan (2 inches deep) with plastic wrap or parchment paper, leaving a 2-inch overhang. Put lined pan in freezer.

Coarsely chop watermelon flesh (leave seeds in), then purée enough to yield 2 1/2 cups in a blender.

Add sugar, juice, and tequila to purée and blend 30 seconds.

Freeze sorbet in ice cream maker.

Transfer to lined baking pan, smoothing top. Put in freezer to harden, at least 1 hour.

Whisk together condensed milk, zest, and juice. Beat cream until it just holds stiff peaks, then gently fold into condensed-milk mixture.

Spread over sorbet, smoothing top. Freeze until solid, at least 2 hours.

To serve, lift dessert from pan using plastic wrap.

Cut into 12 bars and serve on chilled plates.

Dessert can be frozen (covered once completely frozen) up to 3 days.

Cut into bars just before serving.