Combine all marinade ingredients in an immersion blender. Blend until combined well and a few chunks remain.
Pour marinade over steak in a glass dish or a zip top plastic gallon size bag. Allow to marinate for at least 1 hour or up to 4 hours.
Notes
This marinade will also work well on skirt steak, short rib, or sirloin steaks. It's also great for chicken and pork.
About 3-4 oranges will yield 1 cup of freshly squeezed juice. Depending on their size, 2 limes should yield 1/4 cup of juice. I always like to grab an extra one just in case. I don't recommend using pre-bottled orange juice as there are added sugars.
The jalapeno adds a nice dose of spice. Leave the ribs and seeds intact before chopping for more of a kick.
Do note that the nutrition facts listed are for the entire marinade, which you will not consume whole.