Dissapointing Hydrometer results even after mini mash

Had a great brew day with my buddy on Saturday, but the results of our labors were less than optimal IMHO.

This is the second time we've brewed the same recipe, just to see if we could improve or change it somehow. It's a Sierra Nevada clone:

***
Ingredients:

• 8 oz. caramel malt, 30° Lovibond
• 6 oz. DeWolf-Cosyns cara-pils malt
• 6 lbs. light malt syrup
• 1.5 oz. Perle hops (8.2% alpha acid) for 60 min.
• 2.5 oz. Cascade hops (5.4% alpha acid): 1 oz. for 15 min., 1 oz. for 5 min., 0.5
oz. pellets (dry hopping).
• Wyeast 1056 (American ale)
• 11/4 cup dry malt extract

Step by Step:

Add grains to 1.5 gal. water. Bring slowly to 170° F. Remove grains and bring to a boil.
Total boil is 60 min. Boil 10 min. and add Perle hops. Boil 45 min. more, adding water as needed to maintain liquid level. Make first Cascade addition. Boil 5 min. more. Turn off heat. Wait 10 min. Add 1 oz. Cascade. Wait 3 to 5 min. Remove hops and transfer to fermenter.

Top up to 5 gal. Pitch yeast at 70° F.

Ferment three days and rack to secondary. Dry hop with 0.5 oz. Cascade pellets.

Ferment two weeks at 65° F. Prime and bottle.
***

We did this exact recipe about 3 weeks ago and the bottled results of that batch are carbonating right now. We had some to kick off the day but it was still pretty flat. The flavor & body were nice and light; it really complemented the summery day in Seattle. To note, O.G. on the other batch was 1.040.

So the one thing we did different this batch was we did a mini-mash (correct me if I'm using the wrong terminology) using a Mash/Lauter Tun that I made out of a Rubbermaid sports cooler. See here: https://www.homebrewtalk.com/showthread.php?t=23008

We steeped the grains in 1.5 gal of 150 water in the MLT for 1/2 hour, then sparged with .5 gal of 170 water to make a 2 gallon wort boil. The only other thing that we did different was we didn't use hop bags this go-round. Other than that the recipe was performed exactly the same. For some reason our O.G. was only 1.032

It's perking along OK right now but nothing spectacular. I'm just wondering why our starting hydrometer reading was so low. If anything I would have expected our sugar yield to be at least slightly higher with the extended mash time. The wort was mixed up with the water pretty good before we took a reading. Any thoughts as to why OG was low and what will this likely lead to in the end?

I'm far from an expert at this. But you need to steep longer at 150F than you do at 160F in order to convert the starches. I typically do 30 minutes at 160F because I want more body.

At 150F, you'll get a lighter body, but you need to steep for 60 - 90 minutes.

Someone correct me if I'm wrong.

Steeping is not about converting starches.

Steeping is removing colour and flavour.
Mashing is converting starches.

Mashing can be complete in 20 minutes in ideal environments.
Most give it 60 to 90 minutes

You want to be using a base malt and mashing it if you want to increase gravity.

I ran your recipe through ProMash and I get an OG of 1.047. If your final wort volume is 5 gallons and you used 6 pounds of liquid malt, the gravity reading should be pretty close.
Did you mix the wort in the fermenter throughly? Many folks have gotten a low OG reading because they didn't mix the wort enough after adding the top off water to the fermenter. The thicker wort settles to the bottom if it isn't properly stirred.
Also, at what temperature was the wort when you measured it? Most hydrometers are calibrated to 60 degrees F so if the temp was above 60 your reading may have been low.