Fill a large saucepan with water to a depth of 1 inch. Place a steamer basket in saucepan; place beets in basket. Cover, bring to a boil, and steam 12 to 15 minutes or until tender. Drain. Once cool, peel and cut into cubes.
Heat a small skillet over medium-high. Add coriander and mustard seeds; cook 5 minutes or until toasted. Crush toasted seeds with a small heavy skillet until coarsely ground.
Heat olive oil in a large skillet over medium-high. Add beets, crushed seeds, and onion; cook 6 minutes. Reduce heat to medium-low. Add cranberries and next 4 ingredients (through sugar) to pan; cook 20 minutes or until thickened. Stir in salt; cool. Refrigerate in an airtight container up to 1 week.