This cake mix fix-up is best served warm from the oven while the brown sugar topping is still gooey. Cut the cake so each piece includes an apricot half.
Heat oven to 350°F. Grease two 8 x 2-inch swirl cake pans (see Note) with butter. Or, line two 8 x 2-inch round layer-cake pans with foil; butter foil.
Stir butter, sugar, cinnamon and nutmeg in small bowl until sugar is dissolved. Spread over bottoms of pans, dividing equally.
Arrange can of apricots, cut side down, in each pan.
Combine cake mix, butter, sour cream, eggs, sugar and reserved syrup in large bowl. On low, beat 1 minute. Increase speed to medium; beat 2 minutes. Spoon into pans, being careful not to move apricots.
Bake in 350°F oven 45 to 50 minutes, until toothpick tests clean. Let cakes cool in pans on racks 3 minutes. Run knife around edge of cakes; carefully invert onto serving plate; remove pans. Serve slightly warm or at room temperature.