The World Cup holders beat France 2-0 to win the first-ever women’s tournament.
Aleixandri started in midfield for Montserrat Tome’s side in Seville, as strikes from Aitana Bonmati and Mariona Caldentey earned La Roja another title.
Having beaten the Netherlands 3-0 in the semi-finals, Spain came into the final as the favourites but knew they’d need to be at their best against a France side who’d got the better of Germany to reach the showpiece occasion.
But the world champions were on top from the get-go, and Bonmati handed them the lead just after the 30-minute mark when she fired home Olga Carmona’s low ball from the left.
And the lead was doubled soon after the restart from a similar position, when Ona Batlle’s cutback was met by Caldentey.
The Barcelona forward, afforded too much space in the France box, made no mistake, finding the bottom corner of the net beyond the despairing dive of Pauline Peyraud-Magnin.
It was just rewards for Aleixandri and co., who can now add a Nations League winners medal to the trophy cabinet alongside the World Cup crown they achieved last summer.
Kerstin Casparij‘s Holland, meanwhile, had to settle for fourth place in the first-ever Nations League finals.
The Dutch, who had been beaten by Spain in the semi-finals, were beaten 2-0 by Germany in a third-place play-off.
Casparij featured for the full 90 minutes, but second half goals from Klara Buhl and Lea Schuller sealed the win for the Germans.
Elsewhere, Filippa Angeldahl was on target as Sweden cruised past Bosnia & Herzegovina to remain in League A.
The midfielder grabbed her nation’s fourth in a 5-0 rout, having already all but guaranteed they’d remain in the top tier following a first leg triumph by the same margin.
Angeldahl had already grabbed an assist before finding the net, setting up Matilda Vinberg for the game’s opening goal before the 30-minute mark.