Combine milk, 1/4 cup vegetable oil, sugar, egg, instant yeast, salt, and cardamom in a large bowl. Mix in flour, 1 cup at a time, until dough comes together and is easily handled. Knead dough on a flat work surface until no longer sticky.
Put dough back in the bowl, cover, and let rise in a warm area until doubled, about 1 hour.
Press dough down gently. Knead it briefly and divide it into 4 portions. Roll each portion into a ball; keep covered with a cloth to prevent them from drying out.
Roll 1 ball into a 1/3-inch-thick circle on a floured work surface. Cut into 4 triangles using a pizza cutter. Repeat with remaining balls of dough, keeping other dough covered.
Heat oil in a deep-fryer or large saucepan over medium heat. Fry dough triangles 3 or 4 at a time, without overcrowding, until puffed like balloons, 1 to 2 minutes. Turn and continue frying until golden brown, 1 to 2 minutes more. Drain on paper towels. Repeat with remaining dough.
