In a 10- to 12-inch frying pan over medium heat, stir almonds often until golden, about 5 minutes.
Pour from pan and reserve.
Add butter and onion to pan. Stir occasionally until onion is limp, about 5 minutes. Meanwhile, pit and chop 1/2 the dates.
Cut remaining dates lengthwise into 1/2-inch-wide slices; discard pits.
Add rice to onion. Stir often until rice is opaque, about 4 minutes.
Add cumin, ginger, and cardamom; stir 1 minute longer.
Add 1/2 teaspoon salt, broth, and chopped dates. Bring to a boil over high heat, then reduce heat, cover, and simmer, stirring occasionally, until rice is tender to bite, about 15 minutes.
Stir in peas and cook just until they're hot, 1 to 2 minutes.
Pour pilaf into a bowl and top decoratively with sliced dates and almonds.