In a large skillet, heat olive oil over medium heat. Add finely chopped red onion to the skillet. Sautée for 1 minute, stirring occasionally, then add minced garlic and ginger and finely chopped red pepper. Sautée for 1 more minute, stirring occasionally, then add ground cardamom, cloves and a pinch of salt. Sautée for 1 more minute, stirring frequently. Add the lime juice and apple cider vinegar and bring to a boil. Add brown sugar and stir well until it dissolves.

Add the chopped rhubarb and reduce the heat. Cook uncovered until the rhubarb breaks down for a silky texture, or for not more than 4 minutes for a chunky consistency. Add the strawberries and cook until they just begin to soften, for about 2 more minutes. Season with salt and freshly ground black pepper to taste. Let cool and fill into clean/sterilized jars. Enjoy!