This week I pushed the red button for a Hot Fudge Shake, one of 25 shakes for summer at America’s drive-in, Sonic, with 3,500 restaurants across the great expanse.

Sonic’s shakes are made with real ice cream, not some fabricated “dairy product” poured into a concrete mixer that spews artificial everything that they call a milkshake. In fact, my shake was so thick and authentic, they should call it a Hot Sludge Shake. A straw? Stop teasing me. A Dyson vacuum cleaner maybe could suck this shake through a straw.

And it’s a sad state when a restaurant has to brag that it uses actual ice cream in its shakes. But kudos to Sonic for keeping it real. “Real tomato ketchup, Eddie?”

Here’s the blueprint: vanilla ice cream, hot fudge and milk … with whipped cream and a cherry on top.

Total calories: 1,510 for a 28-ounce large. Fat grams: 74. Sodium: 810 mg. Dietary fiber: 4 g. Protein: 20 g. Carbs: 191 g. Manufacturer’s suggested retail price: $4.20. Your mileage may vary.

Many Sonic drive-ins sell their shakes for half-price after 8 p.m. The price is 50 percent off, but the calories and fat grams remain the same. Wow, 1,510 calories and 74 fat grams? That’s all right … I’ll eat again next Thursday. The pure joy of gulping down this shake is worth the regret.

I drank the whole 28-ounce large because I love milkshakes even more than I hate myself for loving milkshakes. Sonic also has a medium-size, 20-ounce cup with “only” 950 calories and 48 fat grams for you dieters. Yeah, right.

Milkshakes are one of the great guilty pleasures — take your time with it. Let it slowly wash over your tongue; savor every drop of sweet chocolate glop before you swallow. I feel a nap coming on.

The boss of Sonic’s research-and-development team must have been on vacation, because the crew has lost its mind coming up with 25 flavors. Among the more devious creations: Peanut Butter & Jelly Shake, Peanut Butter & Bacon (it’s time to evaluate the R&D guys), Coconut Cream Pie and Cherry Cheesecake.

When it comes to shakes, I’m a chocolate fan, and Sonic has eight shakes with my favorite drug (yes, chocolate can hook you): Peanut Butter Fudge, Chocolate Covered Strawberry, Chocolate-Covered Banana, Chocolate Cream Pie, Chocolate Cheesecake, OREO Cheesecake and plain Chocolate. Plus Hot Fudge.

I went with the Hot Fudge Shake because I can’t get enough chocolate. I admit this wasn’t my first time sticking my face into a hot fudge shake. When I visit my local, reasonably priced gourmet ice-cream shop (I have a banana split on layaway), I order my shake with chocolate fudge ice cream. And instead of chocolate syrup, I ask for hot fudge. Forget the whipped cream on top — I want my shake as black as night.

A shake made with hot fudge comes out so thick, I save what I can’t finish and use it to repair potholes on my street.